Source : Webster's Revised Unabridged Dictionary (1913)

Sniff \Sniff\, v. i. [imp. & p. p. {Sniffed}or {Snift}; p. pr. &
   vb. n. {Sniffing}.] [OE. sneven; akin to snivel, snuff; cf.
   Dan. snive to sniff. See {Snuff}, v. t.]
   To draw air audibly up the nose; to snuff; -- sometimes done
   as a gesture of suspicion, offense, or contempt.

         So ye grow squeamish, gods, and sniff at heaven. --M.
                                                  Arnold.

Sniff \Sniff\, v. t.
   1. To draw in with the breath through the nose; as, to sniff
      the air of the country.

   2. To perceive as by sniffing; to snuff, to scent; to smell;
      as, to sniff danger.

Sniff \Sniff\, n.
   The act of sniffing; perception by sniffing; that which is
   taken by sniffing; as, a sniff of air.

Source : WordNet®

sniff
     n : sensing an odor by inhaling through the nose [syn: {snuff}]

sniff
     v 1: perceive by inhaling through the nose; "sniff the perfume"
          [syn: {whiff}]
     2: inhale audibly through the nose; "the sick student was
        sniffling in the back row" [syn: {sniffle}]

Source : Free On-Line Dictionary of Computing

Sniff
     
        A {C++}/{C} programming environment providing browsing,
        cross-referencing, design visualisation, documentation and
        editing support.  Developed by UBS Switzerland and marketed by
        takeFive Salzburg.
     
        [{Jargon File}]

sniff
     
        {poll}