| fitful(adjective, irregular, sporadic) |
| periodic(adjective, uncertain, regular, irregular, broken) |
| intermittent(adjective, uncertain, regular, irregular, routine) |
| sporadic(adjective, off) |
| at different times |
| spotty(adjective, irregular, blotchy) |
| at various times(expression, adjective, idiom, regular, routine) |
| catchy |
| centennial(adjective, regular, routine, sporadic, intermittent) |
| cyclic(adjective, regular, routine, sporadic, intermittent) |
| desultory |
| epochal(adjective, regular, routine, sporadic, intermittent) |
| every once in a while(expression, adjective, idiom, regular, routine) |
| every so often(expression, adjective, idiom, regular, routine) |
| hourly(adjective, regular, routine, sporadic, intermittent) |
| isochronal(adjective, regular, routine, sporadic, intermittent) |
| isochronous(adjective, regular, routine, sporadic, intermittent) |
| monthly(adjective, regular, routine, sporadic, intermittent) |
| on certain occasions(expression, adjective, idiom, regular, routine) |
| orbital(adjective, regular, routine, sporadic, intermittent) |