The Collaborative International Dictionary of English v.0.48:

Streetwalker \Street"walk`er\, n.
   A common prostitute who walks the streets to find customers.
   [1913 Webster]

WordNet (r) 3.0 (2006):

streetwalker
    n 1: a prostitute who attracts customers by walking the streets
         [syn: streetwalker, street girl, hooker, hustler,
         floozy, floozie, slattern]

Moby Thesaurus II by Grady Ward, 1.0:

25 Moby Thesaurus words for "streetwalker":
   B-girl, Cyprian, Paphian, bawd, call girl, cruiser,
   daughter of joy, erring sister, fallen woman, fille de joie,
   harlot, hooker, hustler, meretrix, moll, nightwalker,
   painted woman, poule, prostitute, scarlet woman, stew, tomato,
   unfortunate woman, white slave, whore