The Collaborative International Dictionary of English v.0.48:

Smell \Smell\ (sm[e^]l), v. t. [imp. & p. p. Smelled, Smelt;
   p. pr. & vb. n. Smelling.] [OE. smellen, smillen, smullen;
   cf. LG. smellen, smelen, sm["o]len, schmelen, to smoke, to
   reek, D. smeulen to smolder, and E. smolder. Cf. Smell, n.]
   1. To perceive by the olfactory nerves, or organs of smell;
      to have a sensation of, excited through the nasal organs
      when affected by the appropriate materials or qualities;
      to obtain the scent of; as, to smell a rose; to smell
      perfumes.
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   2. To detect or perceive, as if by the sense of smell; to
      scent out; -- often with out. "I smell a device." --Shak.
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            Can you smell him out by that?        --Shak.
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   3. To give heed to. [Obs.]
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            From that time forward I began to smellthe Word of
            God, and forsook the school doctors.  --Latimer.
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   To smell a rat, to have a sense of something wrong, not
      clearly evident; to have reason for suspicion. [Colloq.]


   To smell out, to find out by sagacity. [Colloq.]
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The Collaborative International Dictionary of English v.0.48:

Smelling \Smell"ing\, n.
   1. The act of one who smells.
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   2. The sense by which odors are perceived; the sense of
      smell. --Locke.
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   Smelling bottle, a small bottle filled with something
      suited to stimulate the sense of smell, or to remove
      faintness, as spirits of ammonia.
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WordNet (r) 3.0 (2006):

smelling
    adj 1: (used with `of' or `with') noticeably odorous; "the hall
           was redolent of floor wax"; "air redolent with the fumes
           of beer and whiskey" [syn: redolent(p), smelling(p)]
    n 1: the act of perceiving the odor of something [syn: smell,
         smelling]