| sporadic(adjective, light, slight, continue, thin) |
| irregular(adjective, chance, casual, rare, variable) |
| casual(adjective, chance, irregular, secondary, erratic) |
| intermittent(adjective, continue, regular, irregular, routine) |
| infrequent(adjective, slight, thin, strange, exceptional) |
| periodic(adjective, continue, regular, irregular, infrequent) |
| uncommon(adjective, slight, thin, strange, exceptional) |
| rare(adjective, slight, thin, exceptional, spare) |
| fitful(adjective, continue, irregular, unreliable, variable) |
| random(adjective, chance, irregular, secondary, erratic) |
| incidental(adjective, chance, irregular, minor, secondary) |
| odd(adjective, irregular, rare, uncommon, infrequent) |
| scarce(adjective, slight, short, usual, irregular) |
| erratic(adjective, chance, irregular, random, haphazard) |
| few(adjective, light, thin, strange, exceptional) |
| episodic(adjective, intermittent, circumstantial) |
| particular(adjective, special, irregular, sporadic) |
| spasmodic(adjective, regular, irregular, routine, unreliable) |
| unusual(adjective, light, thin, exceptional, usual) |
| seldom(adjective, light, slight, thin, strange) |