pollex

Etymology
Borrowed from.

Noun

 * 1) The thumb; the first, or preaxial, digit of the forelimb, corresponding to the hallux in the hind limb. In birds, the pollex is the joint which bears the alula or bastard wing.

Etymology
Of origin.

Traditionally connected to 🇨🇬, with contamination from 🇨🇬 (hence, not ). However, de Vaan is unconvinced, and instead prefers 's derivation from a, from + , with the second syllable in the nominative singular becoming  based on the model of other body parts, such as  inflecting with.

Noun

 * 1) thumb
 * 2) great toe
 * 3) a unit of distance, equivalent to approximately 24.6 mm; one  (see also: Ancient Roman units of measurement)
 * 4) seal (insignia)