镞，或称箭头、箭镞，是箭的组成部分之一。

以有铤双翼青铜镞为例，镞的前锋与关之间的部分统称为镞身，镞身正中突起的部分称为中脊或脊，左右两边称为翼，翼的外缘称为刃，两刃向前聚成前锋，翼最下端为后锋，后锋与中脊相连接处称为本，本与后锋之间的部分为倒刺，其内侧部分称为翼底，中脊最下端与铤相交处称为关，关下部分为铤。

An arrowhead is a tip, usually sharpened, added to an arrow to make it more deadly or to fulfill some special purpose. The earliest arrowheads were made of stone and of organic materials; as human civilization progressed other materials were used. Arrowheads are important archaeological artifacts; they are a subclass of projectile points. Modern enthusiasts still "produce over one million brand-new spear and arrow points per year".