The story
Coined by David Joyce in his 1982 paper A classifying invariant of knots: the knot quandle.
Etymology from Wiktionary, CC BY-SA 4.0.
quandle
Today it means: A rack, scriptstyle Q,, such that scriptstyle ∀a;∈;Q a triangleright a=a or equivalently a triangleleft a=a. Full definition →