unbeknownst
Intermediate (B1)
IPA: /ˌʌnbɪˈnoʊnst/
KK: /ʌnbɪˈnoʊnst/
adjective
Definition
Not known or recognized by someone.
Example
Unbeknownst to her, a surprise party was being planned.
Conversation
Did you hear about the surprise party for Mark?
No, I had no idea! Was it planned for a while?
Yes, it was all set up unbeknownst to him.
Wow, that's impressive! I can't wait to see his reaction.
Synonyms & Antonyms
Synonyms
unknown
unseen
hidden
Antonyms
known
seen
revealed
adverb
Definition
Without the knowledge of someone or something; not known by a particular person or group.
Example
She made plans for the party, unbeknownst to her husband.
Conversation
Did you hear about Sarah's surprise party this weekend?
No, I had no idea! Is it really happening?
Yeah, it's all planned out, unbeknownst to her, of course.
Root Explanation
Unbeknownst is formed from "un-" (meaning not) and "beknown" (from Old English "becnan", meaning to make known). The word describes something that is not known or is unknown to someone.
Memory Tip
Think of 'not' ('un-') knowing something ('beknown') — that's why unbeknownst means something that is not known.
Visually Confused Words
unknownst