The Collaborative International Dictionary of English v.0.48:

Pilfer \Pil"fer\, v. i. [imp. & p. p. Pilfered; p. pr. & vb.
   n. Pilfering.] [OF. pelfrer. See Pelf.]
   To steal in small quantities, or articles of small value; to
   practice petty theft.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Pilfer \Pil"fer\, v. t.
   To take by petty theft; to filch; to steal little by little.
   [1913 Webster]

         And not a year but pilfers as he goes
         Some youthful grace that age would gladly keep.
                                                  --Cowper.
   [1913 Webster]

WordNet (r) 3.0 (2006):

pilfer
    v 1: make off with belongings of others [syn: pilfer,
         cabbage, purloin, pinch, abstract, snarf,
         swipe, hook, sneak, filch, nobble, lift]

Moby Thesaurus II by Grady Ward, 1.0:

62 Moby Thesaurus words for "pilfer":
   abstract, abuse, and, annex, appropriate, bag, befoul, boost,
   borrow, convert, cop, crib, debase, defalcate, defile, defraud,
   desecrate, divert, embezzle, extort, filch, foul, grab, hook, lift,
   make off with, maladminister, misapply, misappropriate, misemploy,
   mishandle, mismanage, misuse, nick, nip, palm, peculate, pervert,
   pinch, plunder, poach, pollute, profane, prostitute, purloin,
   rip off, rob, run away with, rustle, scrounge, shoplift, snaffle,
   snare, snatch, snitch, steal, swindle, swipe, take, thieve,
   violate, walk off with