n. pl. hal·lu·ces (hălyə-sēz′, hălə-)
1. The innermost or first digit on the hind foot of certain mammals. The human hallux is commonly called the big toe.
2. A homologous digit of a bird, reptile, or amphibian. In birds, it is often directed backward.
[Medieval Latin hallux, blend of Latin allus, hallus, thumb, and Latin hallex, big toe.]
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