The Collaborative International Dictionary of English v.0.48:

Transposition \Trans`po*si"tion\, n. [F. transposition, from L.
   transponere, transpositum, to set over, remove, transfer;
   trans across, over + ponere to place. See Position.]
   The act of transposing, or the state of being transposed.
   Specifically:
   [1913 Webster]
   (a) (Alg.) The bringing of any term of an equation from one
       side over to the other without destroying the equation.
       [1913 Webster]
   (b) (Gram.) A change of the natural order of words in a
       sentence; as, the Latin and Greek languages admit
       transposition, without inconvenience, to a much greater
       extent than the English.
       [1913 Webster]
   (c) (Mus.) A change of a composition into another key.
       [1913 Webster]

WordNet (r) 3.0 (2006):

transposition
    n 1: any abnormal position of the organs of the body [syn:
         transposition, heterotaxy]
    2: an event in which one thing is substituted for another; "the
       replacement of lost blood by a transfusion of donor blood"
       [syn: substitution, permutation, transposition,
       replacement, switch]
    3: (genetics) a kind of mutation in which a chromosomal segment
       is transfered to a new position on the same or another
       chromosome
    4: (mathematics) the transfer of a quantity from one side of an
       equation to the other along with a change of sign
    5: (electricity) a rearrangement of the relative positions of
       power lines in order to minimize the effects of mutual
       capacitance and inductance; "he wrote a textbook on the
       electrical effects of transposition"
    6: the act of reversing the order or place of [syn:
       transposition, reversal]
    7: (music) playing in a different key from the key intended;
       moving the pitch of a piece of music upwards or downwards

Moby Thesaurus II by Grady Ward, 1.0:

113 Moby Thesaurus words for "transposition":
   alternation, avatar, battledore and shuttlecock, catabolism,
   catalysis, communication, commutation, conduction,
   consubstantiation, contagion, convection, cooperation,
   counterchange, cross fire, delivery, deportation, diapedesis,
   diffusion, displacement, dissemination, ectropion, eversion,
   exchange, export, exportation, expulsion, extradition,
   give-and-take, heterotopia, import, importation, interchange,
   intermutation, interplay, introversion, intussusception,
   invagination, inversion, lex talionis, measure for measure,
   metabolism, metagenesis, metamorphism, metamorphosis, metastasis,
   metathesis, metempsychosis, migration, mutant, mutated form,
   mutation, mutual admiration, mutual support, mutual transfer,
   mutuality, osmosis, passage, passing over, perfusion, permutation,
   pronation, quid pro quo, reciprocality, reciprocation, reciprocity,
   reincarnation, resupination, retaliation, retroflexion,
   retroversion, reversal, reversing, reversion, revulsion,
   something for something, sport, spread, spreading, supination,
   tit for tat, topsy-turviness, topsy-turvydom, transanimation,
   transduction, transfer, transfer of property, transference,
   transfiguration, transfigurement, transformation, transformism,
   transfusion, transit, transition, translation, translocation,
   transmigration, transmigration of souls, transmission, transmittal,
   transmittance, transmogrification, transmutation, transplacement,
   transplantation, transposal, transubstantiation, travel,
   turning back, turning backwards, turning inside out,
   turning inward, turning over