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infrequent

adjective

happening or occurring at long intervals or rarely: infrequent visits.
not constant, habitual, or regular: an infrequent visitor.
not plentiful or many: infrequent opportunities for advancement.
far apart in space.

adjective

rarely happening or present; only occasional

adj.

1530s, from Latin infrequentem (nominative infrequens) “occurring seldom, unusual,” from in- “not” (see in- (1)) + frequens (see frequent). Related: Infrequently.