Sink v. i. [imp. Sunk or (Sank ); p. p. Sunk (obs. Sunken, -- now used as adj.); p. pr. & vb. n. Sinking.]
  1. To fall by, or as by, the force of gravity; to descend lower and lower; to decline gradually; to subside; as, a stone sinks in water; waves rise and sink; the sun sinks in the west.
     I sink in deep mire.   --Ps. lxix. 2.
  2. To enter deeply; to fall or retire beneath or below the surface; to penetrate.
     The stone sunk into his forehead.   --1 San. xvii. 49.
  3. Hence, to enter so as to make an abiding impression; to enter completely.
     Let these sayings sink down into your ears.   --Luke ix. 44.
  4. To be overwhelmed or depressed; to fall slowly, as so the ground, from weakness or from an overburden; to fail in strength; to decline; to decay; to decrease.
     I think our country sinks beneath the yoke.   --Shak.
     He sunk down in his chariot.   --2 Kings ix. 24.
     Let not the fire sink or slacken.   --Mortimer.
  5. To decrease in volume, as a river; to subside; to become diminished in volume or in apparent height.
     The Alps and Pyreneans sink before him.   --Addison.
  Syn: -- To fall; subside; drop; droop; lower; decline; decay; decrease; lessen.
  sink
       n 1: plumbing fixture consisting of a water basin fixed to a wall
            or floor and having a drainpipe
       2: (technology) a process that acts to absorb or remove energy
          or a substance from a system; "the ocean is a sink for
          carbon dioxide" [ant: source]
       3: a depression in the ground communicating with a subterranean
          passage (especially in limestone) and formed by solution
          or by collapse of a cavern roof [syn: sinkhole, swallow
          hole]
       4: a covered cistern; waste water and sewage flow into it [syn:
           cesspool, cesspit, sump]
       v 1: fall or drop to a lower place or level; "He sank to his
            knees" [syn: drop, drop down]
       2: cause to sink; "The Japanese sank American ships in Pearl
          Harbor"
       3: pass into a specified state or condition; "He sank into
          Nirvana" [syn: pass, lapse]
       4: go under, "The raft sank and its occupants drowned" [syn: settle,
           go down, go under] [ant: float]
       5: descend into or as if into some soft substance or place; "He
          sank into bed"; "She subsided into the chair" [syn: subside]
       6: appear to move downward; "The sun dipped below the horizon";
          "The setting sun sank below the tree line" [syn: dip]
       7: fall heavily or suddenly; decline markedly; "The real estate
          market fell off" [syn: slump, fall off]
       8: fall or sink heavily; "He slumped onto the couch"; "My
          spirits sank" [syn: slump, slide down]
       9: embed deeply; "She sank her fingers into the soft sand"; "He
          buried his head in her lap" [syn: bury]
       [also: sunken, sunk, sank]