plural of unknownness

plural of unknown unknown

An uncertainty of unknown magnitude, consequence, structure, and probability characteristics, possibly with completely unsuspected existence; something that we don't know that we don't know.

The condition of being unknown

(US) Those US military personnel who have died in service, usually in war, without proper burial.

plural of unknown

(sometimes postpositive) Not known; unidentified; not well known.

(algebra) A variable (usually x, y or z) whose value is to be found. / Any thing, place, or situation about which nothing is known; an unknown fact or piece of information.

past participle of unknow

(idiomatic) A person or thing whose nature or value is a mystery. / Used other than figuratively or idiomatically: see unknown, quantity.