Synonyms of unanticipated

1 Syllable
quick
2 Syllables
rushing, abrupt, hasty, sudden, hurried, jerky
3 Syllables
contingent, surprising
4 Syllables
premature, unlooked-for, unpredicted, overearly, precipitous, unexpected, unforeseen, unannounced
5 Syllables
predeveloped, unceremonious, unimagined, precipitate