Synonyms of unplanned

2 Syllables

chanced, unmeant, random, driftless, spoter, aimless, goalless, casual, chancing, chancer, unthought

3 Syllables

spontaneous, unbidden, objectless, unguided, designless, unaimed, impromptu, haphazard, fortuitous, unwitting, impetuous, unhelpful, lucky-dog, hit-or-miss, off-the-cuff

4 Syllables

unintended, unprepared, purposeless, motiveless, aleatory, inadvertent, adventitious, undesigned, accidental, unexpected, coincidental, undirected

5 Syllables

spur-of-the-moment, unpremediated, unmethodical, extemporaneous, unintentional, imperceptive, irreflective, unselective

6 Syllables

indiscriminate, undiscriminating, improvisatory