occasional, sporadic, irregular, intermittent, erratic, spasmodic, fitful, episodic, aperiodic, infrequent, unsteady, odd, episodical, discontinuous, casual, spotty, random, isolated, rare, scarce, choppy, periodic, uncommon, exceptional, unusual, catchy, desultory, incidental, unfrequent, few, chance, especial, sometime, exclusive, particular, special, specific, few and far between, not habitual, off and on, out of the common, semioccasional, abnormal, scattered, unwonted, thin on the ground, unaccustomed, atypical, anomalous, uncustomary … more