Synonyms of onset

1 Syllable

push, dawn, rush, start, birth, dash, raid

2 Syllables

zinger, dawning, advent, blitzkreig, onrush, kickoff, outset, outbreak, dashes, zingers, assault, start-off, jump-off, access, leadoff, jumpoff, source, onslaught, raided, charge, shootup, attack, onfall, outstart, raiding

3 Syllables

encounter, assaulting, rampancy, beginning, aggression, inception, origin, assailment, seizure, aggressions, nascency, opening, offense, drumfire, tipover, nascence

4 Syllables

commencement, curtain-raiser, incipience, ebullition, offensive, incipiency