| makeshift(adjective, free, informal, casual, impulsive) |
| improvisatory(adjective, free, casual, impulsive, spontaneous) |
| on the spot(expression, idiom, occasion, instantaneity, earliness) |
| unscripted(adjective, spontaneous, unprepared, impromptu, unplanned) |
| automatic(adjective, free, simple, fake, natural) |
| extemporarily |
| extemporized(adjective, informal, spontaneous, unprepared, unrehearsed) |
| free(adjective, simple, fake, natural, straightforward) |
| immediately(adverb, instantaneity, earliness) |
| improv(adjective, free, simple, fake, straightforward) |
| improviso(free, casual, impulsive, impulse, spontaneous) |
| instantaneously(adverb, instantaneity, earliness) |
| involuntary(adjective, simple, natural, casual, impulsive) |
| made-up(free, casual, spontaneous, unrehearsed, improvised) |
| out of hand(expression, idiom, earliness) |
| scratch |
| snap(adjective, free, casual, impulsive, prepared) |
| stopgap |
| suddenly(adverb, instantaneity, earliness) |
| accidental(chance, unplanned, unpremeditated) |