FOOTMAN. 1. A member of the infantry as distinguished from the cavalry—horsemen and charioteers. The bulk of ancient armies consisted of footmen.
2. A runner, one of the king’s bodyguard (
Its use in the Pentateuch seems to be broader than just military because of the tribal context. There it is used to contrast between adult men and children.
KJV also uses the word “footman” in a context that calls for the word “guard” (