| Answer | Crossword Clue |
|---|---|
| periodic | Appearing or occurring at intervals |
| intermittent | Occurring at irregular intervals; not continuous or steady |
| irregular | Occurring at uneven or varying rates or intervals |
| hourly | (with numeral or fraction) Occurring at intervals measured in hours |
| unpunctuated | (of a continuing event) Not interrupted or marked by something occurring at intervals |
| nonserial | something appearing in installments at regular intervals |
| serial | something appearing in installments at regular intervals |
