| every so often(expression, idiom, time, moment, regular) |
| from time to time(expression, adverb, time, moment, rare) |
| off and on(expression, idiom, adverb, time, moment) |
| on occasion(expression, time, moment, rare, vacillating) |
| every now and then(expression, adverb, time, moment, rare) |
| now and then(expression, adverb, time, moment, rare) |
| on and off(expression, adverb, time, moment, rare) |
| at intervals(expression, time, rare, vacillating, frequency) |
| once again |
| periodic(expression, adjective, time, regular, rare) |
| at different times |
| here and there(expression, adjective, idiom, time, moment) |
| at various times(expression, adjective, idiom, regular, routine) |
| centennial(adjective, regular, routine, sporadic, intermittent) |
| cyclic(adjective, regular, routine, sporadic, intermittent) |
| epochal(adjective, regular, routine, sporadic, intermittent) |
| hourly(adjective, regular, routine, sporadic, intermittent) |
| intermittent(adjective, regular, routine, sporadic, occasional) |
| isochronal(adjective, regular, routine, sporadic, intermittent) |
| isochronous(adjective, regular, routine, sporadic, intermittent) |