vair n.

mid-14c. (transitive); late 14c. (intransitive), from Old French variier "be changed, go astray; change, alter, transform" and directly from Latin variare "change, alter, make different," from varius "varied, different, spotted;" perhaps related to varus "bent, crooked, knock-kneed," and varix "varicose vein," and, more distantly, to Old English wearte "wart," Swedish varbulde "pus swelling," Latin verruca "wart." Related: Varied; varying.

a type of fur once commonly used for lining and trimming in garments, mid-13c., from Old French menu vair "minor fur;" see menu + vair. The exact description of the thing and meaning of the term is now unclear; according to older French sources, it came from some kind of squirrel.