Definition of erratic :
1. A rogue.
2. Any stone or material that has been borne away from its original site by natural agencies; esp., a large block or fragment of rock; a bowlder.
3. Deviating from a wise of the common course in opinion or conduct; eccentric; strange; queer; as, erratic conduct.
4. Having no certain course; roving about without a fixed destination; wandering; moving; - hence, applied to the planets as distinguished from the fixed stars.
5. Irregular; changeable.
6. One who deviates from common and accepted opinions; one who is eccentric or preserve in his intellectual character.
spaced-out, weirdo, quicksilver, world-wide, occasional, temporary, unsettled, ridiculous, screwy, episodic, quaint, spasmodic, mercurial, unstable, passing, far-out, planetary, off-kilter, changing, continue, out-of-the-way, hit-or-miss, unreliable, ludicrous, mobile, devious, cranky, changeful, unmatched, world, fantastical, usual, varying, remarkable, short-term, scattered, purpose, moody, temperamental, terrestrial, winding, wandering, meandering, funky, unequal, discontinuous, haphazard, floating, screwball, catch-as-catch-can, unpredictable, aperiodic, wacky, kinky, droll, spotty, patchy, grotesque, transient, helter-skelter, roving, kooky, global, short-lived, comical, change, weird, outré, preposterous, planetal, queerish, crotchety, bizarro, rummy, worldwide, rum, catchy, brief, peregrine, wild, slapdash, off-the-wall, choppy, stray, ticklish, unsteady, aimless, same, casual, way-out, rambling, laughable, offbeat, nomadic, unnatural, fantastic
capricious (part of speech: adjective)
agitated (part of speech: adjective)
shaking, skittish, agitated, spastic, restless, upset, nervous, jittery, disquieted, perturbed, shivering, palpitating, quavering, quivering, uneasy, twitching, quaking, fluttered, writhing, wobbling, jumpy, churned, unquiet, convulsive, disturbed, distraught, twitchy, shaken, troubled, jerky, jarred, shuddering, feverish, trembling
irregular (part of speech: adjective)
irresolute (part of speech: adjective)
indecisive, unresolved, halfhearted, changeable, shy, ambivalent, infirm, undecided, unsure, insipid, uncertain, vacillating, shifty, irresolute, spineless, fickle, irresponsible, shilly-shally, yellow, unwilling, capricious, impulsive, dillydallying, shrinking, undependable, watery, fly-by-night, double-minded, weak, volatile, hesitant, tentative, flitting
nonconforming (part of speech: adjective)
freakish, quirky, curious, idiosyncratic, uncustomary, bizarre, unusual, different, incongruous, inconsistent, unconventional, funny, aberrant, un-ordinary, odd, divergent, off, crosspatch, crazy, misfit, deviant, outlandish, atypical, oddball, singular, novel, fey, uncommon, deranged, oddity, queer, incompatible, anomalous, improper, mismatch, strange, eccentric, nonconforming, out of the ordinary, untypical, exceptional, unique, extraordinary, abnormal, peculiar, irregular, unfamiliar
- I am erratic, and careless, and forgetful. - "More About Peggy", Mrs G. de Horne Vaizey.
- We also made several excursions in the neighborhood, in order to study the erratic phenomena and the traces of glaciers, which everywhere cover the surface of the country. - "Louis Agassiz: His Life and Correspondence", Louis Agassiz.
- To this wild doctrine, one erratic Irishman yields a full assent; and, in one American grammatist, we find a partial and unintentional concurrence with it. - "The Grammar of English Grammars", Goold Brown.