'Cheek pouch' definitions:

Definition of 'cheek pouch'

noun

A membranous pouch inside the mouth of many rodents (as a gopher)

From: GCIDE

Cheek \Cheek\ (ch[=e]k), n. [OE. cheke, cheoke, AS. ce[`a]ce, ce[`o]ce; cf. Goth. kukjan to kiss, D. kaak cheek; perh. akin to E. chew, jaw.]
1. The side of the face below the eye. [1913 Webster]
2. The cheek bone. [Obs.] --Caucer. [1913 Webster]
3. pl. (Mech.) Those pieces of a machine, or of any timber, or stone work, which form corresponding sides, or which are similar and in pair; as, the cheeks (jaws) of a vise; the cheeks of a gun carriage, etc. [1913 Webster]
4. pl. The branches of a bridle bit. --Knight. [1913 Webster]
5. (Founding) A section of a flask, so made that it can be moved laterally, to permit the removal of the pattern from the mold; the middle part of a flask. [1913 Webster]
6. Cool confidence; assurance; impudence. [Slang] [1913 Webster]
Cheek of beef. See Illust. of Beef.
Cheek bone (Anat.) the bone of the side of the face; esp., the malar bone.
Cheek by jowl, side by side; very intimate.
Cheek pouch (Zool.), a sacklike dilation of the cheeks of certain monkeys and rodents, used for holding food.
Cheeks of a block, the two sides of the shell of a tackle block.
Cheeks of a mast, the projection on each side of a mast, upon which the trestletrees rest.
Cheek tooth (Anat.), a hinder or molar tooth.
Butment cheek. See under Butment. [1913 Webster]