THESAURUS
rarely
abnormally, at infrequent intervals, exiguously, extremely, hardly, hardly ever, here and there, in places, in spots, incredibly, infrequently, little, meagerly, not often, piddlingly, scantily, scarcely, scarcely ever, scrimpily, seldom, seldom if ever, skimpily, sparsely, sparsim, spottily, stingily, uncommon, uncommonly, uncustomarily, unexpectedly, unfrequently, unnaturally, unoften, unordinarily, unusually, very seldom
ROGET THESAURUS
rarely
Fewness
N
fewness, paucity, small number, small quantity, rarity, infrequency, handful, maniple, minority, exiguity, reduction, weeding, elimination, sarculation, decimation, eradication, few, scant, scanty, thin, rare, scattered, thinly scattered, spotty, few and far between, exiguous, infrequent, rari nantes, hardly any, scarcely any, to be counted on one's fingers, reduced, unrepeated,
rarely, here and there.
Infrequency
N
infrequency, rareness, rarity, fewness, seldomness, uncommonness, unfrequent, infrequent, rare, rare as a blue diamond, few, scarce, almost unheard of, unprecedented, which has not occurred within the memory of the ol, not within one's previous experience, not since Adam, scarce as hen's teeth, one in a million, few and far between, seldom,
rarely, scarcely, hardly, not often, not much, infrequently, unfrequently, unoften, scarcely, scarcely ever, hardly ever, once in a blue moon, once, once in a blue moon, once in a million years, once for all, once in a way, pro hac vice, ein mal kein mal.