The Collaborative International Dictionary of English v.0.48:

Loch \Loch\ (l[o^]k), n. [Gael. & Olr. loch. See Lake of
   water.]
   A lake; a bay or arm of the sea. [Scot.]
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Loch \Loch\ (l[o^]k), n. [F. looch, Ar. la'[=u]g, an electuary,
   or any medicine which may be licked or sucked, fr. la'[=u]q
   to lick.] (Med.)
   A kind of medicine to be taken by licking with the tongue; a
   lambative; a lincture.
   [1913 Webster] Lochaber ax

WordNet (r) 3.0 (2006):

loch
    n 1: a long narrow inlet of the sea in Scotland (especially when
         it is nearly landlocked)
    2: Scottish word for a lake