| breakneck(fast, quick, rapid, speedy, brisk) |
| convertible(adjective, unstable, unsettled, changeable, variable) |
| coquettish(changeable, indecisive, inconsistent) |
| desultory(irregular, unpredictable, unreliable) |
| dizzy(unreliable, changeable, uneven, unbalanced, erratic) |
| dubious(irregular, unpredictable, unreliable, uneven, unbalanced) |
| electric(velocity, excitability) |
| emotional(adjective, nervous, unstable, restless, unreliable) |
| energetic(sharp, lively, fast, sprightly, supple) |
| enthusiastic(nervous, emotional, restless, volatile, fiery) |
| faithless(adjective, changeable, indecisive, inconsistent) |
| flaky(adjective, careless, lively, unstable, unreasonable) |
| flickering(adjective, irregular, changeable, variable) |
| flip(adjective, informal, lively, unpredictable, changeable) |
| frisky |
| frivolous(adjective, impulsive, unpredictable, unreliable, changeable) |
| gaga(adjective, careless, lively, unstable, unreasonable) |
| galvanic(nervous, emotional, restless, volatile, fiery) |
| gay(adjective, lively, impulsive, unpredictable, changeable) |
| headlong(fast, rapid, swift) |