Semiregular

Part of speech: adjective, noun

Definitions

1. Happening at fairly regular intervals but not with strict precision ; having a pattern that is largely consistent yet allows for occasional irregularity
2. Recurring with a rough regularity over time ; showing a form or arrangement that is mostly orderly but not perfectly uniform
3. Taking place at intervals that are roughly predictable ; displaying a partial regularity in structure or sequence rather than complete uniformity

Etymology: "Semiregular" is a plain compound: the prefix "semi-", meaning "half" or "partly", from Latin "sēmi-", attached to "regular". The adjective "regular" came into English from Anglo-Norman and Middle English "reguler", itself from Latin "rēgulāris", which is built on "rēgula", meaning "rule" or "straightedge", the thing that keeps lines straight. So a regular thing is one that keeps to a rule, and a semiregular one keeps to a rule only part of the time or in part of its structure. The prefix "semi-" traces back to the same ancient root that gives "half" in several other languages, and it entered English as a Latin borrowing used freely in forming new compounds. Because it attaches so readily to adjectives, English speakers can combine it with almost any word that describes a pattern.

Synonyms: occasional, periodic, intermittent

Antonyms: regular, constant, permanent