The Collaborative International Dictionary of English v.0.48:

Peddler \Ped"dler\, n. [OE. pedlere, pedlare, also peddare,
   peoddare, fr. OE. ped a basket, of unknown origin.]
   One who peddles; a traveling trader; one who travels about,
   retailing small wares; a hawker. [Written also pedlar and
   pedler.] "Some vagabond huckster or peddler." --Hakluyt.
   [1913 Webster]

WordNet (r) 3.0 (2006):

peddler
    n 1: someone who travels about selling his wares (as on the
         streets or at carnivals) [syn: peddler, pedlar,
         packman, hawker, pitchman]
    2: an unlicensed dealer in illegal drugs [syn: pusher, drug
       peddler, peddler, drug dealer, drug trafficker]

Moby Thesaurus II by Grady Ward, 1.0:

18 Moby Thesaurus words for "peddler":
   arab, cadger, chapman, cheap-jack, cheap-john, cheapjack,
   colporteur, coster, costermonger, duffer, hawker, higgler,
   huckster, monger, pusher, roadman, sidewalk salesman, vendor