A spear is a pole weapon consisting of a shaft, usually of wood, with a pointed head. Spears can be divided into two broad categories: those designed for thrusting and those designed for throwing. Wikipedia
In Wasteland, a Spear is a missile weapon. Repeated use of Spears will raise your Brawling Skill.
A favorite tactic is standing 2 squares away from Brother Goliath in the Guardian Citadel and pelting him with Spears to raise Brawling to level 7 and thus gaining 4 melee attacks per round.