This little glossary from a topic I opened time ago
may be of some help.
Fur - Thief - Looter
Montis Sicaris - Mountain Bandits
Silvae Sicaris - Forest Bandits
Libertus - Freed man, former slave in ancient Rome. I think it now refers to a common serf.
Iaculator - he who throws (missile troop)
Non didicti - something like "those who are not known as", I guess, but I may be wrong
Absolvitor - he who solve, do things.
arcoballista - crossbow
sagittarius - bowmen
Hastatus - man armed with hasta (spearman)
Dux - He who leads, leader
Machaerophorus - He who brings a sword, sword bearer (I think is more greek than latin, anyway)
Gisarme - this is not latin. Kinda halberd, big badass blade
Pedes de cives - citizen infantry
Oppidanus - man from an oppidum (fortification)
Gladius - old short latin sword
Retrobannum - The ban was the king calling for his vassals. The retrobannum was the vassals calling for vavassins and so on.
Vicanus - villager
Servio eques - Serf horseman
Scutifer - Those who brings the shield - squire
Homo armatus - Man-at-arms
Armiger eques - Armiger ahorse
Miles - Knight
Miles and Eques
The word "miles" was originally referred to infantry, while eques was the word for horseman. In the middle-ages
miles started to be referred to knight and general soldiers alike, creating a lot of confusion.