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.
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| # | Word | Details | Meaning | Sample sentence |
|---|---|---|---|---|
| 316 | solution concentration | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: solution + concentration. Study the complete expression as one field-specific unit. | 溶液濃度 | Evaporation increased the solution concentration. |
| 317 | molarity | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Suffix focus: -ity commonly forms a noun naming a quality, state, or condition. | モル濃度 | The beaker contained a molarity of 0.5 moles per liter. |
| 318 | pH scale | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: pH + scale. Study the complete expression as one field-specific unit. | pHスケール | Pure water is near 7 on the pH scale. |
| 319 | acid-base indicator | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: acid + base + indicator. Study the complete expression as one field-specific unit. | 酸塩基指示薬 | Litmus is an acid-base indicator that turns red in acid. |
| 320 | electrolyte | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Base-form focus: electrolyte is the dictionary headword; compare its inflected or derived forms in context. | 1. 電解液 2. 電解質 | Dissolved salt is an electrolyte. |
| 321 | nonelectrolyte | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Prefix focus: non- means not or without. | 非電解質 | Sugar is a nonelectrolyte in water. |
| 322 | oxidation number | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: oxidation + number. Study the complete expression as one field-specific unit. | 酸化数 | Oxygen usually has an oxidation number of negative two. |
| 323 | redox reaction | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: redox + reaction. Study the complete expression as one field-specific unit. | 酸化還元 | Rusting is a redox reaction in which iron loses electrons. |
| 324 | electron transfer | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: electron + transfer. Study the complete expression as one field-specific unit. | 電子移動 | Electron transfer occurs from zinc to copper ions in the cell. |
| 325 | synthesis reaction | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: synthesis + reaction. Study the complete expression as one field-specific unit. | 合成反応 | A synthesis reaction joins hydrogen and oxygen to form water. |
| 326 | decomposition reaction | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: decomposition + reaction. Study the complete expression as one field-specific unit. | 分解反応 | Heating calcium carbonate causes a decomposition reaction. |
| 327 | single-replacement reaction | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: single + replacement + reaction. Study the complete expression as one field-specific unit. | 単一置換反応 | Zinc replacing hydrogen in acid is a single-replacement reaction. |
| 328 | double-replacement reaction | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: double + replacement + reaction. Study the complete expression as one field-specific unit. | 二重置換反応 | The two clear solutions undergo a double-replacement reaction and form a solid. |
| 329 | precipitation reaction | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: precipitation + reaction. Study the complete expression as one field-specific unit. | 沈殿反応 | Mixing silver nitrate and sodium chloride causes a precipitation reaction. |
| 330 | net ionic equation | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: net + ionic + equation. Study the complete expression as one field-specific unit. | 正味のイオン方程式 | The net ionic equation omits ions that remain unchanged. |
| 331 | scalar | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Base-form focus: scalar is the dictionary headword; compare its inflected or derived forms in context. | スカラー | Temperature is a scalar. |
| 332 | vector | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Base-form focus: vector is the dictionary headword; compare its inflected or derived forms in context. | ベクトル | Velocity is a vector because its direction matters. |
| 333 | vector magnitude | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: vector + magnitude. Study the complete expression as one field-specific unit. | ベクトルの大きさ | The arrow's length represents the vector magnitude. |
| 334 | instantaneous velocity | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: instantaneous + velocity. Study the complete expression as one field-specific unit. | 瞬間速度 | The speedometer approximates the car's instantaneous velocity. |
| 335 | average acceleration | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: average + acceleration. Study the complete expression as one field-specific unit. | 平均加速度 | The runner's average acceleration was greatest during the first two seconds. |
| 336 | linear momentum | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: linear + momentum. Study the complete expression as one field-specific unit. | 線形運動量 | A moving truck has more linear momentum than a bicycle at the same speed. |
| 337 | impulse | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Base-form focus: impulse is the dictionary headword; compare its inflected or derived forms in context. | 1. 衝撃 2. 推進力 | An air bag extends the stopping time and changes the passenger's momentum with a smaller impulse force. |
| 338 | rotational inertia | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: rotational + inertia. Study the complete expression as one field-specific unit. | 回転慣性 | Moving mass farther from an axis increases rotational inertia. |
| 339 | force equilibrium | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: force + equilibrium. Study the complete expression as one field-specific unit. | 力の平衡 | A hanging lamp at rest is in force equilibrium. |
| 340 | frictional force | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: frictional + force. Study the complete expression as one field-specific unit. | 摩擦力 | The frictional force between shoes and the floor prevents slipping. |
| 341 | gravitational force | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: gravitational + force. Study the complete expression as one field-specific unit. | 重力 | Earth's gravitational force pulls the ball downward. |
| 342 | normal force | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: normal + force. Study the complete expression as one field-specific unit. | 通常の力 | The table's normal force balances the book's weight. |
| 343 | applied force | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: applied + force. Study the complete expression as one field-specific unit. | 加えられた力 | The worker's applied force moved the crate across the floor. |
| 344 | tension force | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: tension + force. Study the complete expression as one field-specific unit. | 張力 | The cable's tension force supports the elevator. |
| 345 | free-body diagram | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: free + body + diagram. Study the complete expression as one field-specific unit. | 自由体図 | The free-body diagram includes gravity, support, and friction. |
| 346 | Newton's first law | proper noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: Newton's + first + law. Study the complete expression as one field-specific unit. | ニュートンの第1法則 | Newton's first law explains why a puck keeps sliding on nearly frictionless ice. |
| 347 | Newton's second law | proper noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: Newton's + second + law. Study the complete expression as one field-specific unit. | ニュートンの第2法則 | Newton's second law predicts greater acceleration when the same mass receives a larger force. |
| 348 | Newton's third law | proper noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: Newton's + third + law. Study the complete expression as one field-specific unit. | ニュートンの第3法則 | Newton's third law pairs the swimmer's push on water with water's push on the swimmer. |
| 349 | conservation of momentum | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: conservation + of + momentum. Study the complete expression as one field-specific unit. | 運動量の保存 | Conservation of momentum explains the motion of two skaters who push apart. |
| 350 | elastic collision | noun StudyField: Grade 9 physical, Earth, and environmental-science term Word study: Term structure: elastic + collision. Study the complete expression as one field-specific unit. | 弾性衝突 | An ideal elastic collision allows two hard spheres to rebound without losing kinetic energy. |
Vocabulary reading and practice
Forces and Solutions
Reading practice for pages 10–12. Five relevant words are highlighted.
English reading
A beaker rests on a scale while gravitational force pulls it downward and normal force from the scale pushes upward. Inside, a precipitation reaction forms a solid from two clear solutions. The chemist describes each solution concentration with molarity, the number of moles of dissolved substance per liter of solution.
Japanese translation
A reviewed translation is not available for this passage yet.
Reading comprehension
1. Which force pulls the beaker downward?
Gravitational force pulls it downward.
2. What forms during a precipitation reaction?
A solid forms from the solutions.
3. What does molarity measure?
Molarity measures moles of solute per liter of solution.
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).

