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Webster 1828 Edition

Noun.

mouz'er. One that catches mice. The cat is a good mouser.

mouser ‎(plural mousers)

A cat that catches mice, kept specifically for the purpose.
(chiefly Scotland, US) A moustache.
- 1932, Lewis Grassic Gibbon, Sunset Song, Polygon 2006 (A Scots Quair), p. 20:
  He was a pretty man, well upstanding, with great shoulders on him and his hair was fair and fine and he had a broad brow and a gey bit coulter of a nose and he twisted his mouser ends up with wax like that creature the German Kaiser […].

cat that catches mice

mouser ‎(plural mousers)