The Collaborative International Dictionary of English v.0.48:

Fishmonger \Fish"mon`ger\, n.
   A dealer in fish.
   [1913 Webster]

WordNet (r) 3.0 (2006):

fishmonger
    n 1: someone who sells fish [syn: fishmonger, fishwife]

Moby Thesaurus II by Grady Ward, 1.0:

31 Moby Thesaurus words for "fishmonger":
   baker, bookdealer, bookseller, butcher, chandler,
   clothing merchant, confectioner, draper, drysalter, fishwife,
   florist, footwear merchant, fruiterer, furnisher, furrier,
   greengrocer, grocer, groceryman, haberdasher, hardwareman,
   ironmonger, jeweler, liquor merchant, newsdealer, perfumer,
   poulterer, saddler, stationer, tobacconist, vintner,
   wine merchant