Sentence:  Every bone in the real duck had its representative in the automaton, and its wings were anatomically exact. Every cavity, <WSD>apophysis</WSD>, and curvature was imitated, and each bone executed its proper movements. 
Meaning of the word marked with <WSD> tags:  A natural outgrowth, swelling or enlargement, usually of an organism; A protuberance on a bone.