- unbeknown, unbeknownst - (usually used with `to') occurring or existing without the knowledge of; "a crisis unbeknown to me"; "she had been ill for months, unbeknownst to the family"
Antonym: known (indirect, via unknown)
- unbeknown, unbeknownst - without someone's knowledge; "unbeknownst to me, she made all the arrangements"