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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.

He’s picked up other key endorsements, too, from the California Teachers Assn.,

From Los Angeles Times • May 6, 2026

Inmate votes were especially key in the 2024 gubernatorial primary as González-Colón, a longtime New Progressive Party member, was challenging the incumbent governor of the same party.

From Salon • May 6, 2026

While Maguire believes that Town could expel the demons of their last time in the top flight and survive relegation, he said recruitment would be key.

From BBC • May 6, 2026

DeepSeek has since become a key component of China’s plan to have top-class homegrown companies in a range of AI fields.

From The Wall Street Journal • May 6, 2026

“And she wants to stop the Shadow Queen from getting back to Rio Luna. That’s why we guard each key, but she was getting too close.”

From "The Way to Rio Luna" by Zoraida Cordova

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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