quandle

English

Etymology

Coined by David Joyce in his 1982 paper A classifying invariant of knots: the knot quandle.

Noun

quandle (plural quandles)

1. (mathematics) A rack, $\scriptstyle \mathrm {Q} \,$, such that $\scriptstyle \forall a\;\in \;\mathrm {Q}$ $a\triangleright a=a$ or equivalently $a\triangleleft a=a$.