Easton's Bible Dictionary
A cleft hoof as of neat cattle (Exodus 10:26; Ezek. 32:13); hence also of the horse, though not cloven (Isaiah 5:28). The "parting of the hoof" is one of the distinctions between clean and unclean animals (Leviticus 11:3; Deuteronomy 14:7).
Noah Webster's New International Dictionary of the English Language
1. (n.) The horny substance or case that covers or terminates the feet of certain animals, as horses, oxen, etc.
2. (n.) A hoofed animal; a beast.
3. (n.) See Ungula.
4. (v. i.) To walk as cattle.
5. (v. i.) To be on a tramp; to foot.