master key

NOUN

key opening all locks of a place

Synonyms

WEAK

opener pass'-partout passkey skeleton key

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.

Professor Jonathan Heeney of Cambridge University likened the new technique to having the "master key" for an apartment block.

From Barron's • Jun. 25, 2026

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

I had the master key because another one of my summer jobs was assistant apprentice super for my family’s complex.

From "The Epic Fail of Arturo Zamora" by Pablo Cartaya