[1] : The Collaborative International Dictionary of English v.0.48

ulcer \ul"cer\, n. f. ulc`ere, l. ulcus, gen. ulceris, akin
   to gr. ?.
   1. med. a solution of continuity in any of the soft parts
      of the body, discharging purulent matter, found on a
      surface, especially one of the natural surfaces of the
      body, and originating generally in a constitutional
      disorder; a sore discharging pus. it is distinguished from
      an abscess, which has its beginning, at least, in the
      depth of the tissues.
      1913 webster

   2. fig.: anything that festers and corrupts like an open
      sore; a vice in character.
      1913 webster

   cold ulcer med., an ulcer on a finger or toe, due to
      deficient circulation and nutrition. in such cases the
      extremities are cold.
      1913 webster
see also:
cold ulcer 

[2] : The Collaborative International Dictionary of English v.0.48

ulcer \ul"cer\, v. t.
   to ulcerate. r. --fuller.
   1913 webster

[3] : WordNet (r) 2.0

ulcer
     n : a circumscribed inflammatory and often suppurating lesion on
         the skin or an internal mucous surface resulting in
         necrosis of tissue syn: ulceration
see also:
ulceration 

[4] : Moby Thesaurus II by Grady Ward, 1.0

81 moby thesaurus words for "ulcer":
   abdominal hernia, abscess, aposteme, bane, bed sore, blain, bleb,
   blight, blister, boil, bubo, bulla, bunion, cancer, canker,
   canker sore, carbuncle, chancre, chancroid, chilblain, cold sore,
   colitis, curse, disease, diverticulitis, diverticulosis,
   duodenal ulcer, duodenitis, eruption, eschar, esophagal ulcer,
   esophagitis, felon, fester, festering, fever blister, fistula,
   furuncle, furunculus, gastritis, gathering, gumboil, hemorrhoids,
   hiatal hernia, inflammation, kibe, lesion, megacolon, papula,
   papule, paronychia, parulis, peptic ulcer, peritonitis, pestilence,
   petechia, piles, pimple, plague, pock, poison, polyp, pustule,
   rising, scab, scourge, soft chancre, sore, stigma, stomach ulcer,
   sty, suppuration, swelling, tubercle, ulceration, wale, welt,
   wheal, whelk, whitlow, wound

Ulcer >> U Words
Ulcer, definition of term: Ulcer
ulcer_pag1.html

Peptic Ulcer >> P Words
Peptic Ulcer, definition of term: Peptic Ulcer
peptic+ulcer_pag1.html

Decubitus Ulcer >> D Words
Decubitus Ulcer, definition of term: Decubitus Ulcer
decubitus+ulcer_pag1.html