The Collaborative International Dictionary of English v.0.48:

Grocer \Gro"cer\, n. [Formerly written grosser, orig., one who
   sells by the gross, or deals by wholesale, fr. F. grossier,
   marchand grossier, fr. gros large, great. See Gross.]
   A trader who deals in foods such as meats, dairy products,
   produce, tea, sugar, spices, coffee, fruits, and various
   other commodities.
   [1913 Webster]

   Grocer's itch (Med.), a disease of the skin, caused by
      handling sugar and treacle.
      [1913 Webster]

WordNet (r) 3.0 (2006):

grocer
    n 1: a retail merchant who sells foodstuffs (and some household
         supplies)

Moby Thesaurus II by Grady Ward, 1.0:

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