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9th-grade-vocabulary-words

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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800 words
Words 456–490 of 800
#WordDetailsMeaningSample sentence
456residualnoun
Study

Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Base-form focus: residual is the dictionary headword; compare its inflected or derived forms in context.

1. restant 2. résiduA positive residual means the observation lies above the prediction.
457residual plotnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: residual + plot. Study the complete expression as one field-specific unit.

tracé résiduelA curved pattern in the residual plot suggests that a linear model is unsuitable.
458interpolationnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Suffix focus: -ation commonly forms a noun naming an action, process, or result.

interpolationInterpolation estimates the temperature between two recorded times.
459two-column proofnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: two + column + proof. Study the complete expression as one field-specific unit.

preuve sur deux colonnesThe two-column proof pairs each angle claim with a definition or theorem.
460paragraph proofnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: paragraph + proof. Study the complete expression as one field-specific unit.

preuve de paragrapheThe paragraph proof explains why corresponding parts of the triangles are congruent.
461logical statementnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: logical + statement. Study the complete expression as one field-specific unit.

déclaration logique“Seven is prime” is a true logical statement.
462conditional statementnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: conditional + statement. Study the complete expression as one field-specific unit.

instruction conditionnelleThe conditional statement says that if an angle is right, then it measures ninety degrees.
463conversenoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Base-form focus: converse is the dictionary headword; compare its inflected or derived forms in context.

réciproqueThe converse of “if it is a square, then it is a rectangle” is not always true.
464inversenoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Base-form focus: inverse is the dictionary headword; compare its inflected or derived forms in context.

contraireThe inverse does not necessarily share the original statement's truth value.
465contrapositivenoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Base-form focus: contrapositive is the dictionary headword; compare its inflected or derived forms in context.

contraposéeA conditional and its contrapositive are logically equivalent.
466biconditionalnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Base-form focus: biconditional is the dictionary headword; compare its inflected or derived forms in context.

biconditionnelA biconditional can be written with the phrase “if and only if.”
467truth valuenoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: truth + value. Study the complete expression as one field-specific unit.

valeur de véritéA counterexample proves that the universal statement has a false truth value.
468axiomatic systemnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: axiomatic + system. Study the complete expression as one field-specific unit.

axiomatiqueEuclidean geometry is an axiomatic system.
469congruence theoremnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: congruence + theorem. Study the complete expression as one field-specific unit.

théorème de congruenceThe side-angle-side congruence theorem proves the triangles match.
470similarity theoremnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: similarity + theorem. Study the complete expression as one field-specific unit.

théorème de similaritéThe angle-angle similarity theorem applies to the two triangles.
471triangle congruencenoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: triangle + congruence. Study the complete expression as one field-specific unit.

congruence triangulaireThree corresponding side lengths can establish triangle congruence.
472angle relationshipnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: angle + relationship. Study the complete expression as one field-specific unit.

relation angulaireThe diagram shows an angle relationship between alternate interior angles.
473parallel linenoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: parallel + line. Study the complete expression as one field-specific unit.

ligne parallèleEach rail is a parallel line relative to the other.
474algorithmic procedurenoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: algorithmic + procedure. Study the complete expression as one field-specific unit.

procédure algorithmiqueThe sorting program follows an algorithmic procedure.
475pseudocodenoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Base-form focus: pseudocode is the dictionary headword; compare its inflected or derived forms in context.

pseudo-codeThe pseudocode states when the loop should stop.
476flowchartnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Base-form focus: flowchart is the dictionary headword; compare its inflected or derived forms in context.

organigrammeThe flowchart sends a failed login back to the password step.
477variable declarationnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: variable + declaration. Study the complete expression as one field-specific unit.

déclaration de variableThe variable declaration reserves storage for the score.
478data typenoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: data + type. Study the complete expression as one field-specific unit.

1. type de données 2. typeA Boolean data type stores true or false.
479Booleannoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Capitalization focus: Boolean is conventionally capitalized because the term comes from the name George Boole.

1. booléen 2. boolienThe comparison returns a Boolean.
480conditional branchnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: conditional + branch. Study the complete expression as one field-specific unit.

branche conditionnelleThe conditional branch displays an error when the password is incorrect.
481loopnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Base-form focus: loop is the dictionary headword; compare its inflected or derived forms in context.

boucleThe loop processes every item in the list.
482loop iterationnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: loop + iteration. Study the complete expression as one field-specific unit.

itération de boucleDuring each loop iteration, the index increases by one.
483debuggingnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Base-form focus: debugging is the dictionary headword; compare its inflected or derived forms in context.

1. débuggage 2. débogageDebugging revealed that the program compared text instead of numbers.
484compilernoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Base-form focus: compiler is the dictionary headword; compare its inflected or derived forms in context.

compilateurThe compiler reported a missing bracket.
485interpreternoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Base-form focus: interpreter is the dictionary headword; compare its inflected or derived forms in context.

1. interpréteur 2. interprèteThe interpreter stopped when it encountered an undefined name.
486source codenoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: source + code. Study the complete expression as one field-specific unit.

1. code source 2. source 3. sourcesThe developer reviewed the source code before releasing the update.
487object codenoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: object + code. Study the complete expression as one field-specific unit.

code objetThe compiler converted the program into object code.
488network securitynoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: network + security. Study the complete expression as one field-specific unit.

sécurité du réseauNetwork security includes firewalls, monitoring, and controlled permissions.
489data encryptionnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Term structure: data + encryption. Study the complete expression as one field-specific unit.

cryptage des donnéesData encryption protects the message while it travels across the network.
490decryptionnoun
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Field: Grade 9 mathematics, computing, and data-literacy term

Word study: Suffix focus: -tion commonly forms a noun naming an action, process, or result.

décryptageAuthorized decryption requires the correct key.

Vocabulary reading and practice

Page 14 vocabulary review

Review five selected words from page 14.

Vocabulary quiz

Choose the dictionary equivalent for each of 5 selected words.

Sources and curriculum references

These references guide selection and calibration. Definitions, sample sentences, readings, questions, and teaching notes are independently written and reviewed.