† ˈdiallelObs.—0. [ad.Gr. διάλληλος through one another.] (See quot.) 1656Blount Glossogr.s.v., As parallels are lines running one by the other without meeting: so Diallels are lines which run one through the other, that is, do cross, intersecate, or cut. [Hence in Bailey, Ash, etc.].