The Collaborative International Dictionary of English v.0.48:

Abscess \Ab"scess\ ([a^]b"s[e^]s), n.; pl. Abscesses
   ([a^]b"s[e^]s*[e^]z). [L. abscessus a going away, gathering
   of humors, abscess, fr. abscessus, p. p. of absedere to go
   away; ab, abs + cedere to go off, retire. See Cede.] (Med.)
   A collection of pus or purulent matter in any tissue or organ
   of the body caused by infection.
   [1913 Webster + AS]

   Cold abscess,
   (a) an abscess of slow formation, unattended with the pain
       and heat characteristic of ordinary abscesses, and
       lasting for years without exhibiting any tendency towards
       healing; a chronic abscess. AS
   (b) an abscess produced by tubercle bacilli, called also
       tuberculous abscess. --AS
       [1913 Webster + AS]

WordNet (r) 3.0 (2006):

abscess
    n 1: symptom consisting of a localized collection of pus
         surrounded by inflamed tissue

Moby Thesaurus II by Grady Ward, 1.0:

129 Moby Thesaurus words for "abscess":
   ague, anemia, ankylosis, anoxia, apnea, aposteme, asphyxiation,
   asthma, ataxia, atrophy, backache, bed sore, blain, bleb, bleeding,
   blennorhea, blister, blotch, boil, bubo, bulla, bunion, cachexia,
   cachexy, canker, canker sore, carbuncle, chancre, chancroid,
   chilblain, chill, chills, cold sore, colic, constipation,
   convulsion, coughing, cyanosis, diarrhea, dizziness, dropsy,
   dysentery, dyspepsia, dyspnea, edema, emaciation, eschar, fainting,
   fatigue, felon, fester, festering, fever, fever blister,
   fibrillation, fistula, flux, furuncle, furunculus, gathering,
   growth, gumboil, hemorrhage, hemorrhoids, high blood pressure,
   hydrops, hypertension, hypotension, icterus, indigestion,
   inflammation, insomnia, itching, jaundice, kibe, labored breathing,
   lesion, low blood pressure, lumbago, marasmus, nasal discharge,
   nausea, necrosis, pain, papula, papule, paralysis, paronychia,
   parulis, petechia, piles, pimple, pock, polyp, pruritus, pustule,
   rash, rheum, rising, scab, sclerosis, seizure, shock,
   skin eruption, sneezing, soft chancre, sore, spasm, stigma, sty,
   suppuration, swelling, tabes, tachycardia, trauma, tubercle, tumor,
   ulcer, ulceration, upset stomach, vertigo, vomiting, wale, wasting,
   welt, wheal, whelk, whitlow, wound