[1] : The Collaborative International Dictionary of English v.0.48

porthole \port"hole`\, n. naut.
   an embrasure in a ship's side. see 3d port.
   1913 webster
see also:
port 

[2] : WordNet (r) 2.0

porthole
     n 1: a window in a ship or airplane
     2: an opening in a wall or ship or armored vehicle for firing
        through syn: port, embrasure
see also:
port embrasure 

[3] : Moby Thesaurus II by Grady Ward, 1.0

53 moby thesaurus words for "porthole":
   air hole, armhole, bay, bay window, blowhole, bow window,
   bullet-hole, bunghole, casement, casement window, cringle, deadeye,
   eye, eyelet, fan window, fanlight, gasket, grille, grommet, guide,
   keyhole, knothole, lancet window, lantern, lattice, light, loop,
   loophole, louver window, manhole, mousehole, oriel, pane, peephole,
   picture window, pigeonhole, pinhole, placket, placket hole, port,
   punch-hole, rose window, skylight, spiracle, tap, transom, vent,
   venthole, wicket, window, window bay, window glass, windowpane

Porthole >> P Words
Porthole, definition of term: Porthole
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