crows-nest

from The Collaborative International Dictionary of English v.0.48

crow's-nest \crow's"-nest`\, crow's nest \crow's"
nest`\(kr[=o]z"n[e^]st`), n. (Naut.)
   A box or platform near the top of a mast, esp. in whalers, to
   shelter the man on the lookout.
   [1913 Webster]