hallux
\ HAL-uhks \, noun;
1.the first or innermost digit of the foot of humans and other primates or of the hind foot of other mammals; great toe; big toe.
2.the comparable, usually backward-directed digit in birds.
Quotes:
All fingers and toes, except the hallux , have claws. The hallux has a flat nail which is opposable to the others.
-- Eman P. Fridman and Ronald D. Nadler, Medical Primatology: History, Biological Foundations and Applications , 2002
The four toes are in line with the first (big) toe (the hallux ), unlike the toes of other apes (humans are considered apes), in which the hallux is offset from the remaining toes.
-- Jeremy Rich, Dorothy E. Dean, and Robert H. Powers, Forensic Medicine of the Lower Extremity , 2005
Origin:
Hallux entered English in the 1820s. It is a corruption of the Latin word allex meaning "great toe."
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