The Collaborative International Dictionary of English v.0.48:
Armless \Arm"less\, a. 1. Without any arm or branch. [1913 Webster] 2. Destitute of arms or weapons. [1913 Webster]WordNet (r) 3.0 (2006):
armless adj 1: having no arms; "the armless Venus de Milo" [ant: armed]