un-

Ⅰ.

un- [1] ► PREFIX 1) (added to adjectives, participles, and their derivatives) denoting the absence of a quality or state; not: unacademic. 2) the reverse of: unselfish. 3) (added to nouns) a lack of: untruth.

USAGE The prefixes un- and non- both mean ‘not’, but are used with a difference of emphasis, un- being stronger and less neutral than non-. Compare, for example, unacademic and non-academic in his language was refreshingly unacademic and a non-academic life suits him .

ORIGIN Old English.

Ⅱ.

un- [2] ► PREFIX added to verbs: 1) denoting the reversal or cancellation of an action or state: unsettle. 2) denoting deprivation, separation, or reduction to a lesser state: unmask. 3) denoting release: unhand.

ORIGIN Old English.