| temporal(adjective, transient) |
| temporary(adjective, transient) |
| unexpected(adjective, sudden, surprising) |
| volatile(adjective, transient) |
| accelerated(adjective, fast, rapid, swift, sudden) |
| alacritous |
| alert(fast, precise, responsive, early, rapid) |
| clamant(adjective, prompt, fast, quick, immediate) |
| compact(rapid, swift, instant) |
| compendious(rapid, swift, instant) |
| concise(rapid, swift, instant) |
| crying(prompt, fast, quick, immediate, urgent) |
| curt(fast, rapid, swift, instant) |
| discontinuous(adjective, instantaneity) |
| exigent(adjective, prompt, fast, quick, immediate) |
| extemporaneous(adjective, impulsive) |
| hair-trigger(adjective, immediate) |
| headlong(adjective, fast, summary, rapid, swift) |
| impetuous(adjective, fast, rapid, swift, sudden) |
| impulsive(adjective, impulsive, sudden) |