English

equiregular

From equi- + regular.

Old Latin aiquos

Latin aequus ‘equal’

English equi-

Proto-Indo-European *h₃reǵ- ‘move in a straight line’

Latin rēgula ‘rule’

Latin rēgulāris ‘continuing rules for guidance’

Anglo-Norman reguler

Middle English reguler

Today it means

adj Containing elements that are both outer regular and inner regular and which have inverses that are also both outer regular and inner regular.

Language periods are conventional ranges, not dates for this word.

Etymograph / equiregular