INFREQUENTLY
infrequently
(adverb) not many times; “in your 1850 church you not infrequently find a dramatic contrast between the sumptuous appointments of the building itself and the inhuman barrack-like living conditions in the church room”
Source: WordNet® 3.1
Etymology
Adverb
infrequently (comparative more infrequently, superlative most infrequently)
Not frequently.
Synonyms
• seldom
Antonyms
• frequently
• often
Source: Wiktionary
In*fre"quent*ly, adv.
Definition: Not frequently; rarely.
INFREQUENT
In*fre"quent, a. Etym: [L. infrquens : cf.F. infrequent. See In- not,
and Frequent.]
Definition: 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.
Source: Webster’s Unabridged Dictionary 1913 Edition