The Collaborative International Dictionary of English v.0.48:

Mutual \Mu"tu*al\, a. [F. mutuel, L. mutuus, orig., exchanged,
   borrowed, lent; akin to mutare to change. See Mutable.]
   1. Reciprocally acting or related; reciprocally receiving and
      giving; reciprocally given and received; reciprocal;
      interchanged; as, a mutual love, advantage, assistance,
      aversion, etc.
      [1913 Webster]

            Conspiracy and mutual promise.        --Sir T. More.
      [1913 Webster]

            Happy in our mutual help,
            And mutual love.                      --Milton.
      [1913 Webster]

            A certain shyness on such subjects, which was mutual
            between the sisters.                  --G. Eliot.
      [1913 Webster]

   2. Possessed, experienced, or done by two or more persons or
      things at the same time; common; joint; as, mutual
      happiness; a mutual effort. --Burke.
      [1913 Webster]

            A vast accession of misery and woe from the mutual
            weeping, and wailing, and gnashing of teeth.
                                                  --Bentley.
      [1913 Webster]

   Note: This use of mutual as synonymous with common is
         inconsistent with the idea of interchange, or
         reciprocal relation, which properly belongs to it; but
         the word has been so used by many writers of high
         authority. The present tendency is toward a careful
         discrimination.
         [1913 Webster]

               Mutual, as Johnson will tell us, means something
               reciprocal, a giving and taking. How could people
               have mutual ancestors?             --P. Harrison.
         [1913 Webster]

   Mutual insurance, agreement among a number of persons to
      insure each other against loss, as by fire, death, or
      accident.

   Mutual insurance company, one which does a business of
      insurance on the mutual principle, the policy holders
      sharing losses and profits pro rata.
      [1913 Webster]

   Syn: Reciprocal; interchanged; common.
        [1913 Webster]

WordNet (r) 3.0 (2006):

mutual
    adj 1: common to or shared by two or more parties; "a common
           friend"; "the mutual interests of management and labor"
           [syn: common, mutual]
    2: concerning each of two or more persons or things; especially
       given or done in return; "reciprocal aid"; "reciprocal
       trade"; "mutual respect"; "reciprocal privileges at other
       clubs" [syn: reciprocal, mutual] [ant: nonreciprocal]

Moby Thesaurus II by Grady Ward, 1.0:

94 Moby Thesaurus words for "mutual":
   accessory, accompanying, associated, attendant, attending,
   changeable, coacting, coactive, coadjutant, coadjuvant,
   coefficient, coincident, collaborative, collateral, collective,
   collectivist, collectivistic, collusive, combined, commensal,
   common, communal, communalist, communalistic, communist,
   communistic, communitarian, commutable, commutative, commutual,
   complementary, concerted, concomitant, concordant, concurrent,
   concurring, conjoint, conjunct, connected, conniving, convertible,
   cooperant, cooperating, cooperative, correlative, coupled,
   ecumenic, equal, equalizing, equivalent, even, exchanged, fellow,
   general, give-and-take, harmonious, harmonized, in common,
   interactive, interchangeable, interchanged, joined, joint,
   noncompetitive, paired, parallel, permutable, popular, public,
   reciprocal, reciprocating, reciprocative, related, respective,
   retaliatory, returnable, shared, simultaneous, social, socialistic,
   societal, standard, swapped, switched, symbiotic, synergetic,
   synergic, synergistic, traded, transposed, twin, two-way,
   uncompetitive, united



U.S. Gazetteer Places (2000):

Mutual, OH -- U.S. village in Ohio
   Population (2000):    132
   Housing Units (2000): 51
   Land area (2000):     0.136140 sq. miles (0.352600 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    0.136140 sq. miles (0.352600 sq. km)
   FIPS code:            53480
   Located within:       Ohio (OH), FIPS 39
   Location:             40.079243 N, 83.638167 W
   ZIP Codes (1990):
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Mutual, OH
    Mutual


U.S. Gazetteer Places (2000):

Mutual, OK -- U.S. town in Oklahoma
   Population (2000):    76
   Housing Units (2000): 38
   Land area (2000):     0.262126 sq. miles (0.678902 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    0.262126 sq. miles (0.678902 sq. km)
   FIPS code:            50150
   Located within:       Oklahoma (OK), FIPS 40
   Location:             36.229816 N, 99.167704 W
   ZIP Codes (1990):     73853
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Mutual, OK
    Mutual