Webster's Revised Unabridged Dictionary · 1913

Infrequent

Infrequent , adjective

[Latin infrequens: compare French infrequent. See In- not, and Frequent.]

Seldom happening or occurring; rare; uncommon; unusual.
The act whereof is at this day infrequent or out of use among all sorts of men. — Sir T. Elyot