The Collaborative International Dictionary of English v.0.48:

Cabin \Cab"in\ (k[a^]b"[i^]n), n. [OF. caban, fr. W. caban
   booth, cabin, dim. of cab cot, tent; or fr. F. cabane,
   cabine, LL. cabanna, perh. from the Celtic.]
   1. A cottage or small house; a hut. --Swift.
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            A hunting cabin in the west.          --E. Everett.
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   2. A small room; an inclosed place.
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            So long in secret cabin there he held
            Her captive.                          --Spenser.
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   3. A room in ship for officers or passengers.
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   Cabin boy, a boy whose duty is to wait on the officers and
      passengers in the cabin of a ship.
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WordNet (r) 3.0 (2006):

cabin boy
    n 1: a young man acting as a servant on a ship