| extemporaneous(adjective, unprepared, unplanned, unintentional, accidental) |
| haphazard(adjective, unprepared, unplanned, unintentional, accidental) |
| inadvertent(adjective, planned, unplanned, unintentional, accidental) |
| undesigned(adjective, planned, unplanned, unintentional, accidental) |
| unintended(adjective, planned, unplanned, unintentional, accidental) |
| unintentional(adjective, planned, unplanned, accidental, inadvertent) |
| unplanned(adjective, planned, unintentional, accidental, inadvertent) |
| impromptu(adjective, unprepared) |
| improvised(adjective, unprepared) |
| makeshift(adjective, unprepared) |
| rough-and-ready(adjective, unprepared) |
| unmeant(adjective, planned, unintentional) |
| unpremeditated(adjective, unplanned, unintentional, accidental, inadvertent) |
| unprepared(adjective, unprepared) |
| unthought(adjective, unplanned, unintentional, accidental, inadvertent) |
| unwitting(adjective, planned, unplanned, unintentional, accidental) |
| accidental(adjective, unplanned, unintentional, inadvertent) |
| aimless(adjective, unplanned, unintentional, accidental, inadvertent) |
| casual(adjective, unplanned, unintentional, accidental, inadvertent) |
| chance(adjective, unplanned, unintentional, accidental, inadvertent) |