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Definitions

key

[kee] / ki /
ADJECTIVE
essential, important
Synonyms
STRONGEST
basic crucial decisive fundamental indispensable leading main major pivotal primary principal vital
STRONG
chief material
Antonyms
STRONGEST
additional auxiliary extra inessential insignificant lesser minor nonessential secondary subordinate trivial unimportant unnecessary
NOUN
item that unlocks
Synonyms
STRONG
latchkey opener passkey screw skeleton
Antonyms
WEAK
lock question
NOUN
answer, solution
Synonyms
STRONGEST
blueprint clue code core guide indicator means passport password sign ticket
STRONG
brand cipher crux cue earmark explanation fulcrum hinge index interpretation lead lever marker nexus nucleus pivot pointer root symptom translation
Antonyms
STRONG
exterior exteriority outside
WEAK
lock question

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Bowler Ollie Robinson has been in contact with both England head coach Brendon McCullum and managing director Rob Key as he eyes a recall to the Test side.

From BBC • May 4, 2026

Key details: A narrower measure of inflation that omits food and energy rose a lesser 0.3% in March.

From MarketWatch • Apr. 30, 2026

Key catalysts include model upgrades, potential inclusion into stock indexes and an A-share listing.

From The Wall Street Journal • Apr. 30, 2026

Around 1990, Coe’s contract with Columbia ended and amid personal troubles including a divorce and trouble with the IRS, his Key West, Fla., home was seized.

From Los Angeles Times • Apr. 30, 2026

I didn’t know if I would be discovered, but Key West certainly had been.

From Full of Beans by Jennifer L. Holm

Vocabulary lists containing key

Jim Burke's Academic Vocabulary List

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TEKS ELAR Academic Vocabulary List (5th-7th grades)

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Music - Introductory

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