[1] : WordNet (r) 2.0

unbeknownst
     adj : 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" syn: unbeknownp,
            unbeknownstp
     adv : without someone's knowledge; "unbeknownst to me, she made
           all the arrangements" syn: unbeknown
see also:
unbeknownp unbeknownstp unbeknown 

Unbeknownst >> U Words
Unbeknownst, definition of term: Unbeknownst
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