| quick(noun, adjective, passionate, violent, irritable) |
| serendipitous(adjective, chance, unplanned) |
| sudden(noun, adjective, passionate, violent, careless) |
| unarranged(adjective, spontaneous, unprepared, unplanned, unrehearsed) |
| undevised(adjective, unplanned, unintentional, accidental, inadvertent) |
| unexpected(adjective, passionate, violent, careless, casual) |
| unguided |
| unmeant(adjective, rude, careless, casual, thoughtless) |
| unorganized(adjective, careless, casual, arbitrary) |
| unpredictable(noun, adjective, passionate, violent, thoughtless) |
| visceral(adjective, natural, instinctive, automatic, involuntary) |
| ad hoc(expression, adjective, free, casual, unrehearsed) |
| adventitious(adjective, chance, haphazard, unplanned, accidental) |
| arbitrary(adjective, careless, chance, casual, random) |
| blundering(adjective, rude, careless, thoughtless, unwise) |
| careless(adjective, passionate, violent, casual, thoughtless) |
| caught napping(expression, idiom, nonpreparation) |
| gut(ignorant, hidden, unconscious, unaware, oblivious) |
| improv(free, informal, casual, spontaneous, unprepared) |
| improvisatory(free, informal, casual, impulsive, impulse) |