What is "mouse piece"

Mouse \Mouse\ (mous), n.; pl. Mice (m[imac]s). [OE. mous, mus, AS. m[=u]s, pl. m[=y]s; akin to D. muis, G. maus, OHG. & Icel. m[=u]s, Dan. muus, Sw. mus, Russ. muishe, L. mus, Gr. my^s, Skr. m[=u]sh mouse, mush to steal. [root]277. Cf. Muscle, Musk.]

1. (Zo["o]l.) Any one of numerous species of small rodents belonging to the genus Mus and various related genera of the family Murid[ae]. The common house mouse ( Mus musculus) is found in nearly all countries. The American white-footed mouse, or deer mouse ( Peromyscus leucopus, formerly Hesperomys leucopus) sometimes lives in houses. See Dormouse, Meadow mouse, under Meadow, and Harvest mouse, under Harvest.

2. (Naut.)

   1. A knob made on a rope with spun yarn or parceling to prevent a running eye from slipping.

   2. Same as 2d Mousing, 2.

3. A familiar term of endearment.
   --Shak.

4. A dark-colored swelling caused by a blow. [Slang]

5. A match used in firing guns or blasting. Field mouse, Flying mouse, etc. See under Field, Flying, etc. Mouse bird (Zo["o]l.), a coly. Mouse deer (Zo["o]l.), a chevrotain, as the kanchil. Mouse galago (Zo["o]l.), a very small West American galago ( Galago murinus). In color and size it resembles a mouse. It has a bushy tail like that of a squirrel. Mouse hawk. (Zo["o]l.)

   1. A hawk that devours mice.

   2. The hawk owl; -- called also mouse owl.

      Mouse lemur (Zo["o]l.), any one of several species of very small lemurs of the genus Chirogaleus, found in Madagascar.

      Mouse piece (Cookery), the piece of beef cut from the part next below the round or from the lower part of the latter; -- called also mouse buttock.