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Definitions

master key

NOUN
key opening all locks of a place
Synonyms


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.

Antibodies can sometimes act like a master key, helping trigger immune responses.

From Science Daily • Jan. 9, 2026

Mitchell also went into Blanchard’s chambers in 2023 by using a master key, the commission wrote.

From Los Angeles Times • Feb. 13, 2025

Why it's important: Your SSN is a master key to your financial life.

From Salon • Aug. 27, 2024

Fitzwater has also become a member of Crohn's and Colitis UK, who have given him a special card and a master key which allows him to access more than 9,000 locked public toilets.

From BBC • Feb. 15, 2024

“They must have some way to let people in. Do they have a master key in the office?”

From "Tangerine" by Edward Bloor