The Collaborative International Dictionary of English v.0.48:

Admit \Ad*mit"\, v. t. [imp. & p. p. Admitted; p. pr. & vb. n.
   Admitting.] [OE. amitten, L. admittere, admissum; ad +
   mittere to send: cf. F. admettre, OF. admettre, OF. ametre.
   See Missile.]
   1. To suffer to enter; to grant entrance, whether into a
      place, or into the mind, or consideration; to receive; to
      take; as, they were into his house; to admit a serious
      thought into the mind; to admit evidence in the trial of a
      cause.
      [1913 Webster]

   2. To give a right of entrance; as, a ticket admits one into
      a playhouse.
      [1913 Webster]

   3. To allow (one) to enter on an office or to enjoy a
      privilege; to recognize as qualified for a franchise; as,
      to admit an attorney to practice law; the prisoner was
      admitted to bail.
      [1913 Webster]

   4. To concede as true; to acknowledge or assent to, as an
      allegation which it is impossible to deny; to own or
      confess; as, the argument or fact is admitted; he admitted
      his guilt.
      [1913 Webster]

   5. To be capable of; to permit; as, the words do not admit
      such a construction. In this sense, of may be used after
      the verb, or may be omitted.
      [1913 Webster]

            Both Houses declared that they could admit of no
            treaty with the king.                 --Hume.
      [1913 Webster]

WordNet (r) 3.0 (2006):

admit
    v 1: declare to be true or admit the existence or reality or
         truth of; "He admitted his errors"; "She acknowledged that
         she might have forgotten" [syn: admit, acknowledge]
         [ant: deny]
    2: allow to enter; grant entry to; "We cannot admit non-members
       into our club building"; "This pipe admits air" [syn:
       admit, allow in, let in, intromit] [ant: refuse,
       reject, turn away, turn down]
    3: allow participation in or the right to be part of; permit to
       exercise the rights, functions, and responsibilities of;
       "admit someone to the profession"; "She was admitted to the
       New Jersey Bar" [syn: admit, let in, include] [ant:
       exclude, keep out, shut, shut out]
    4: admit into a group or community; "accept students for
       graduate study"; "We'll have to vote on whether or not to
       admit a new member" [syn: accept, admit, take, take
       on]
    5: afford possibility; "This problem admits of no solution";
       "This short story allows of several different
       interpretations" [syn: admit, allow]
    6: give access or entrance to; "The French doors admit onto the
       yard"
    7: have room for; hold without crowding; "This hotel can
       accommodate 250 guests"; "The theater admits 300 people";
       "The auditorium can't hold more than 500 people" [syn:
       accommodate, hold, admit]
    8: serve as a means of entrance; "This ticket will admit one
       adult to the show"

Moby Thesaurus II by Grady Ward, 1.0:

187 Moby Thesaurus words for "admit":
   Americanize, Anglicize, O, OK, accept, accord, acculturate,
   acculturize, acknowledge, acquiesce, acquire, admit everything,
   admit exceptions, adopt, affiliate, agree, agree provisionally,
   allow, allow for, assent, assent grudgingly, assimilate, assume,
   avow, barge in, be admitted, break in, breeze in, brook, burst in,
   bust in, come barging in, come breezing in, come busting in,
   come by, come clean, come in, come in for, complete, comprehend,
   comprise, concede, confer citizenship, confess, consent, consider,
   consider the circumstances, consider the source, contain,
   cop a plea, count in, cover, creep in, cross the threshold,
   crowd in, declare, derive, derive from, discount, dispense,
   disregard, divulge, drag down, draw, draw from, drop in, edge in,
   embody, embrace, encircle, enclose, encompass, enter, entertain,
   envisage, express general agreement, fill, fill in, fill out, gain,
   gain admittance, get, get in, give an entree, give leave,
   give permission, give the go-ahead, give the word, go along with,
   go in, go into, go native, grant, harbor, have, have an entree,
   have an in, have coming in, hold, hop in, house, immit, include,
   incorporate, induct, initiate, insert, install, interject,
   interpose, introduce, intromit, intrude, irrupt, jam in, jump in,
   leave, let, let in, let on, lift temporarily, lodge, look in,
   make allowance for, make possible, naturalize, not oppose,
   number among, obtain, occupy, okay, open up, out with it, own,
   own up, pack in, permit, plead guilty, pop in, press in,
   provide for, pull down, push in, put in, receive, reckon among,
   reckon in, reckon with, recognize, relax, relax the condition,
   release, reveal, say the word, secure, set aside, set foot in,
   shelter, slip in, spill, spill it, spit it out, squeeze in,
   step in, subscribe, suffer, take, take account of,
   take cognizance of, take in, take into account,
   take into consideration, take on, take over, take up, tell all,
   tell the truth, throw open to, thrust in, tolerate, visit,
   vouchsafe, waive, warrant, wedge in, work in, yield