English Vocabulary · Grade 9 Live Review Preview
9th Grade Vocabulary Words
Ninth grade marks the transition to high-school reading and writing across literature, argument, research, biology, physical and Earth science, algebra, computing, world history, civics, and geography. This level develops precise academic and domain-specific vocabulary while strengthening context, nuance, source evaluation, figurative language, and evidence-based communication.
This independently authored 800-word beta curriculum is arranged in twenty-three pages of up to thirty-five words. Pages containing words 1–500 include five cloze questions drawn only from that enhanced range; words 501–800 remain fully visible and editable as list pages while the expanded practice layer is developed. Each row includes a subject-field label and an editable word-study note about a transparent affix, compound structure, capitalization, or dictionary base form. The cited Grade 9 resources calibrate difficulty and study skills only; all learner-facing definitions, examples, quizzes, and descriptions are original KSSR copy.
Please note: the vocabulary lists for grades 9~11 have been selected to ensure no overlap with the previous grade level. If the words are too specialized or difficult for you, please go back to grade levels 4~8 and review the words on those pages.
Open the basic text version — works without JavaScript and is suitable for printing.
Your private study tools
Track your learning with My Vocabulary
Use the three small controls beside any word. Your choices stay attached to your account and appear in your My Vocabulary record.
- Star a difficult word to practise it again.
- Check a word when you have learned it.
- Add a note with a memory clue, synonym, or reminder.
These controls work during your free visits and save privately on this browser. Sign in to move them into your account’s My Vocabulary record.
| # | Word | Details | Meaning | Sample sentence |
|---|---|---|---|---|
| 351 | inelastic collision | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: inelastic + collision. Study the complete expression as one field-specific unit. | colisão inelástica | Cars that crumple together undergo an inelastic collision. |
| 352 | work-energy theorem | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: work + energy + theorem. Study the complete expression as one field-specific unit. | teorema da energia do trabalho | The work-energy theorem connects the pushing force with the cart's increased speed. |
| 353 | ideal mechanical advantage | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: ideal + mechanical + advantage. Study the complete expression as one field-specific unit. | vantagem mecânica ideal | A longer input arm increases a lever's ideal mechanical advantage. |
| 354 | conservation of energy | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: conservation + of + energy. Study the complete expression as one field-specific unit. | conservação de energia | Conservation of energy means the pendulum's potential and kinetic energy trade places. |
| 355 | gravitational potential energy | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: gravitational + potential + energy. Study the complete expression as one field-specific unit. | energia potencial gravitacional | Lifting the backpack increases its gravitational potential energy. |
| 356 | elastic potential energy | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: elastic + potential + energy. Study the complete expression as one field-specific unit. | energia potencial elástica | A drawn bow contains elastic potential energy. |
| 357 | wave frequency | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: wave + frequency. Study the complete expression as one field-specific unit. | frequência de onda | Increasing wave frequency raises the pitch of a sound. |
| 358 | wave amplitude | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: wave + amplitude. Study the complete expression as one field-specific unit. | amplitude da onda | A louder sound usually has greater wave amplitude. |
| 359 | wave period | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: wave + period. Study the complete expression as one field-specific unit. | período de onda | A two-hertz wave has a wave period of half a second. |
| 360 | wave speed | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: wave + speed. Study the complete expression as one field-specific unit. | velocidade da onda | Wave speed depends on the medium through which the disturbance moves. |
| 361 | transverse wave | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: transverse + wave. Study the complete expression as one field-specific unit. | onda transversal | A wave on a stretched rope can be a transverse wave. |
| 362 | longitudinal wave | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: longitudinal + wave. Study the complete expression as one field-specific unit. | onda longitudinal | Sound in air travels as a longitudinal wave. |
| 363 | constructive interference | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: constructive + interference. Study the complete expression as one field-specific unit. | interferência construtiva | Two crests meeting create constructive interference. |
| 364 | destructive interference | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: destructive + interference. Study the complete expression as one field-specific unit. | interferência destrutiva | A crest meeting a trough can cause destructive interference. |
| 365 | wave refraction | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: wave + refraction. Study the complete expression as one field-specific unit. | refração de onda | Wave refraction bends light as it enters glass. |
| 366 | wave reflection | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: wave + reflection. Study the complete expression as one field-specific unit. | reflexão de onda | An echo results from wave reflection. |
| 367 | standing wave | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: standing + wave. Study the complete expression as one field-specific unit. | onda estacionária | A vibrating guitar string forms a standing wave. |
| 368 | natural frequency | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: natural + frequency. Study the complete expression as one field-specific unit. | frequência natural | The tuning fork rings at its natural frequency. |
| 369 | Doppler effect | proper noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: Doppler + effect. Study the complete expression as one field-specific unit. | efeito Doppler | The Doppler effect makes an approaching siren sound higher. |
| 370 | electromagnetic spectrum | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: electromagnetic + spectrum. Study the complete expression as one field-specific unit. | 1. espectro eletromagnético 2. espectro electromagnético | Visible light occupies a small part of the electromagnetic spectrum. |
| 371 | igneous rock | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: igneous + rock. Study the complete expression as one field-specific unit. | 1. rocha ígnea 2. pedra ígnea | Granite is an igneous rock that cooled slowly underground. |
| 372 | sedimentary rock | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: sedimentary + rock. Study the complete expression as one field-specific unit. | rocha/pedra sedimentar/sedimentária | Sandstone is a sedimentary rock made from cemented sand grains. |
| 373 | metamorphic rock | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: metamorphic + rock. Study the complete expression as one field-specific unit. | 1. pedra metamórfica 2. rocha metamórfica | Marble is a metamorphic rock formed from limestone. |
| 374 | rock weathering | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: rock + weathering. Study the complete expression as one field-specific unit. | intemperismo rochoso | Freezing water causes rock weathering by widening cracks. |
| 375 | sediment deposition | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: sediment + deposition. Study the complete expression as one field-specific unit. | deposição de sedimentos | Slower river water causes sediment deposition near the mouth. |
| 376 | soil horizon | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: soil + horizon. Study the complete expression as one field-specific unit. | horizonte do solo | Dark organic material is common in the upper soil horizon. |
| 377 | tectonic theory | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: tectonic + theory. Study the complete expression as one field-specific unit. | teoria tectônica | Tectonic theory accounts for matching earthquake belts and plate boundaries. |
| 378 | continental movement | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: continental + movement. Study the complete expression as one field-specific unit. | movimento continental | Fossil evidence helped scientists reconstruct continental movement. |
| 379 | seafloor spreading | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: seafloor + spreading. Study the complete expression as one field-specific unit. | expansão do fundo do mar | Magnetic stripes provide evidence for seafloor spreading. |
| 380 | convergent boundary | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: convergent + boundary. Study the complete expression as one field-specific unit. | limite convergente | A deep trench can form at a convergent boundary. |
| 381 | divergent boundary | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: divergent + boundary. Study the complete expression as one field-specific unit. | limite divergente | New crust forms at an oceanic divergent boundary. |
| 382 | transform boundary | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: transform + boundary. Study the complete expression as one field-specific unit. | limite de transformação | Shallow earthquakes are common along a transform boundary. |
| 383 | earthquake focus | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: earthquake + focus. Study the complete expression as one field-specific unit. | foco do terremoto | Seismic waves spread outward from the earthquake focus. |
| 384 | moment magnitude | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: moment + magnitude. Study the complete expression as one field-specific unit. | magnitude do momento | The moment magnitude scale compares the energy of large earthquakes. |
| 385 | volcanic hotspot | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: volcanic + hotspot. Study the complete expression as one field-specific unit. | ponto de acesso vulcânico | An island chain formed as a plate moved over a volcanic hotspot. |
Vocabulary reading and practice
Page 11 vocabulary review
Review five selected words from page 11.
English reading
Reading passage is being prepared.
Portuguese translation
A reviewed translation is not available for this passage yet.
Vocabulary quiz
Choose the dictionary equivalent for each of 5 selected words.
Vocabulary chart page
This page focuses on the word chart. Reading passages appear once in each three-page group, while cloze quizzes remain in the established enhanced range for this level.
Sources and curriculum references
These references guide selection and calibration. Definitions, sample sentences, readings, questions, and teaching notes are independently written and reviewed.
- GreatSchools: 9th Grade Vocabulary Words
- Victoria University of Wellington: Coxhead Academic Word List
- Common Core: Language Standards for Grades 9–10
- Common Core: Science and Technical Subjects, Grades 9–10
- WikDict downloadable bilingual dictionaries
- Kaikki.org / Wiktextract machine-readable Wiktionary data
- Language-Learning-decks public flashcard datasets
- SBBIC English-to-Khmer Dictionary
- English–Khmer Dictionary Dataset (machine-generated Khmer fallback; human review required)
- PanLex meanings snapshot (direct CC0 gap candidates; human review required)
- Cambridge bilingual dictionaries (individual editorial sense checks)
- Collins English–Hindi Dictionary (individual editorial checks)
- Hindwi and Rekhta dictionaries (individual Hindi/Urdu checks)
- National Institute of Korean Language: Basic Korean Dictionary
- JMdict/EDRDG Japanese dictionary project
- CC-CEDICT Chinese dictionary project
- VDict Vietnamese Dictionary (individual editorial check)
- Google Translate (machine-assisted lesson-reading draft; fluent review required)
- Kuperman et al.: Age-of-acquisition ratings for 30,000 English words
- The Princeton Review, Word Smart (2006 and 2012 editions; bibliographic calibration only).

