Another word for irregular
uneven, spasmodic, fitful, uncertain, erratic, variable, aberrant, random, unsettled, inconstant, unsteady, fragmentary, unsystematic, occasional, infrequent, fluctuating, faltering, wavering, recurrent, intermittent, discontinuous, sporadic, changeable, capricious, casual, shifting, unmethodical, unreliable, unpredictable, jerky, up and down*; see also changing, unsteady 2.
Not regular in form or outline
not uniform, crooked, devious, unsymmetrical, asymmetrical, nonsymmetrical, uneven, unequal, craggy, hilly, broken, jagged, aberrant, notched, serrate, eccentric, elliptic, elliptical, bumpy, meandering, zigzagged, bent, unaligned, amorphous, variable, wobbly, lumpy, off balance, off center, protuberant, lopsided, pockmarked, scarred, crinkled, bristling, bumpy, sprawling, out of proportion, flawed, damaged, imperfect, cockeyed*, gallywampus*; see also bent, crooked 1.
irregular implies deviation from the customary or established rule, procedure, etc. irregular conduct; abnormal and anomalous imply deviation from the normal condition or from the ordinary type, abnormal stressing atypical form or character a man of abnormal height, and anomalous, stressing an exceptional condition or circumstance in the anomalous position of a leader without followers; unnatural applies to that which is contrary to the order of nature or to natural laws an unnatural appetite for chalk