The Collaborative International Dictionary of English v.0.48:

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]

The Collaborative International Dictionary of English v.0.48:

Cheek \Cheek\ (ch[=e]k), v. t.
   To be impudent or saucy to. [Slang.]
   [1913 Webster]

WordNet (r) 3.0 (2006):

cheek
    n 1: either side of the face below the eyes
    2: an impudent statement [syn: impudence, cheek,
       impertinence]
    3: either of the two large fleshy masses of muscular tissue that
       form the human rump [syn: buttock, cheek]
    4: impudent aggressiveness; "I couldn't believe her boldness";
       "he had the effrontery to question my honesty" [syn:
       boldness, nerve, brass, face, cheek]
    v 1: speak impudently to

Moby Thesaurus II by Grady Ward, 1.0:

72 Moby Thesaurus words for "cheek":
   arse, ass, backside, bank, beam, behind, border, bottom, brashness,
   brass, brazen boldness, breech, broadside, bum, butt, can, cheeks,
   chop, chutzpah, coast, confidence, crust, derriere, duff, face,
   fanny, flank, gall, hand, handedness, haunch, heroics, hip, hubris,
   improvidence, imprudence, impudence, indiscretion, injudiciousness,
   insolence, jowl, keister, laterality, many-sidedness,
   multilaterality, nerve, overboldness, overcarelessness,
   overconfidence, oversureness, overweeningness, planking, prat,
   presumption, profile, quarter, rashness, rusty-dusty, shore, side,
   siding, stern, tail, temerariousness, temerity, temple, tuchis,
   tush, tushy, unchariness, unilaterality, unwariness



Easton's 1897 Bible Dictionary:

Cheek
   Smiting on the cheek was accounted a grievous injury and insult
   (Job 16:10; Lam. 3:30; Micah 5:1). The admonition (Luke 6:29),
   "Unto him that smiteth thee on the one cheek offer also the
   other," means simply, "Resist not evil" (Matt. 5:39; 1 Pet.
   2:19-23). Ps. 3:7 = that God had deprived his enemies of the
   power of doing him injury.