| improvize |
| invent(verb, make, fix, plan, create) |
| off the cuff(expression, adjective, idiom, adverb, manner) |
| unplanned(adjective, free, simple, fake, informal) |
| unstudied(adjective, free, simple, fake, natural) |
| extemporization(noun, planned, prepared, improvised, improvisation) |
| makeshift(adjective, free, simple, casual, spontaneous) |
| spontaneously(adverb, manner, improv, extemporaneously) |
| unpremeditated(free, spontaneous, unprepared, impromptu, unplanned) |
| unwritten |
| vamp(verb, plan, create, arrange, design) |
| ad libitum(expression, adjective, adverb, informal, unplanned) |
| automatic(adjective, free, simple, fake, passionate) |
| cook up(verb, expression, make, fix, plan) |
| extemporized(adjective, fake, informal, spontaneous, unprepared) |
| fake it(verb, expression, craft, make, fix) |
| hasty(thoughtless, impetuous, unwary) |
| improv(verb, adjective, adverb, make, fix) |
| knock off(verb, expression, make, fix, produce) |
| play by ear(verb, expression, idiom, make, fix) |