adj

unbeknownst

uhn-bih-NOHNST

Unbeknownst (adj) means Without the knowledge of someone; unknown to them. Example: “Unbeknownst to his parents, he had already dropped the class.”

adj

Without the knowledge of someone; unknown to them.

"Unbeknownst to his parents, he had already dropped the class."

How to use unbeknownst

Learner’s notes

In plain EnglishHappening without a particular person knowing about it.

When to use it

Almost always used in the fixed phrase "unbeknownst to [someone]," and leans slightly formal or literary.

Common pairings

unbeknownst to him unbeknownst to us

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_____ to his parents, he had already dropped the class.

Etymology

A variant of the older word "unbeknown," with an extra "-st" added the same way it was tacked onto words like "amongst" and "amidst."

Frequently asked questions

What does “unbeknownst” mean?

The word “unbeknownst” means without the knowledge of someone; unknown to them. In plain terms, happening without a particular person knowing about it.

How do you pronounce “unbeknownst”?

“Unbeknownst” is pronounced uhn-bih-NOHNST (/ˌʌnbɪˈnoʊnst/ in IPA).

How do you use “unbeknownst” in a sentence?

Here is “unbeknownst” used in a sentence: “Unbeknownst to his parents, he had already dropped the class.”

What part of speech is “unbeknownst”?

“Unbeknownst” is an adjective.