NOUN (3)

1. a medical establishment run by a group of medical specialists;

2. meeting for diagnosis of problems and instruction or remedial work in a particular activity;

3. a healthcare facility for outpatient care;

The Collaborative International Dictionary of English v.0.48:

Clinical \Clin"ic*al\ (kl[i^]n"[i^]k*al), Clinic \Clin"ic\
   (kl[i^]n"[i^]k), a. [Gr. kliniko`s, fr. kli`nh bed, fr.
   kli`nein to lean, recline: cf. F. clinique. See Lean, v.
   i.]
   1. Of or pertaining to a bed, especially, a sick bed.
      [1913 Webster]

   2. Of or pertaining to a clinic, or to the study of disease
      in the living subject.
      [1913 Webster]

   Clinical baptism, baptism administered to a person on a
      sick bed.

   Clinical instruction, instruction by means of clinics.

   Clinical lecture (Med.), a discourse upon medical topics
      illustrated by the exhibition and examination of living
      patients.

   Clinical medicine, Clinical surgery, that part of
      medicine or surgery which is occupied with the
      investigation of disease in the living subject.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Clinic \Clin"ic\, n. [See Clinical.]
   1. One confined to the bed by sickness.
      [1913 Webster]

   2. (Eccl.) One who receives baptism on a sick bed. [Obs.]
      --Hook.
      [1913 Webster]

   3. (Med.) a medical facility, often connected with a school
      or hospital, which treats primarily outpatients.
      [PJC]

   4. (Med.) A school, or a session of a school or class, in
      which medicine or surgery is taught by the examination and
      treatment of patients in the presence of the pupils.
      [1913 Webster]

   5. a lesson or series of lessons taught to persons not expert
      in some activity, in which the errors of the students are
      pointed out, and remedial actions are suggested.
      [PJC]

   6. (sports) a performance so excellent as to be considered a
      model for emulation. [fig.]
      [PJC] Clinical

WordNet (r) 3.0 (2006):

clinic
    n 1: a medical establishment run by a group of medical
         specialists
    2: meeting for diagnosis of problems and instruction or remedial
       work in a particular activity
    3: a healthcare facility for outpatient care

Moby Thesaurus II by Grady Ward, 1.0:

61 Moby Thesaurus words for "clinic":
   VA hospital, X ray, asylum, base hospital, blood bank,
   charity ward, community hospital, consultation room,
   convalescent home, convalescent hospital, delivery room,
   dispensary, emergency, evacuation hospital, examining room,
   fever ward, field hospital, general hospital, home, hospital,
   hospital room, infirmary, inpatient clinic, intensive care,
   isolation, labor room, laboratory, maison de sante, maternity ward,
   mental hospital, nursery, nursing home, operating room,
   osteopathic hospital, outpatient clinic, pharmacy, policlinic,
   polyclinic, prison ward, private hospital, private room,
   proprietary hospital, public hospital, recovery room, rest home,
   sanatorium, semi-private room, sick bay, sickbed, sickroom,
   special hospital, station hospital, surgery, surgical hospital,
   teaching hospital, therapy, treatment room, veterans hospital,
   voluntary hospital, ward, well-baby clinic