The Collaborative International Dictionary of English v.0.48:

Inflection \In*flec"tion\, n. [L. inflexio : cf. F. inflexion.
   See Inflect.] [Written also inflecxion.]
   1. The act of inflecting, or the state of being inflected.
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   2. A bend; a fold; a curve; a turn; a twist.
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   3. A slide, modulation, or accent of the voice; as, the
      rising and the falling inflection.
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   4. (Gram.) The variation or change which words undergo to
      mark case, gender, number, comparison, tense, person,
      mood, voice, etc.
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   5. (Mus.)
      (a) Any change or modification in the pitch or tone of the
          voice.
      (b) A departure from the monotone, or reciting note, in
          chanting.
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   6. (Opt.) Same as Diffraction.
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   Point of inflection (Geom.), the point on opposite sides of
      which a curve bends in contrary ways.
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WordNet (r) 3.0 (2006):

inflection
    n 1: a change in the form of a word (usually by adding a suffix)
         to indicate a change in its grammatical function [syn:
         inflection, inflexion]
    2: the patterns of stress and intonation in a language [syn:
       prosody, inflection]
    3: deviation from a straight or normal course [syn:
       inflection, flection, flexion]
    4: a manner of speaking in which the loudness or pitch or tone
       of the voice is modified [syn: modulation, inflection]

Moby Thesaurus II by Grady Ward, 1.0:

96 Moby Thesaurus words for "inflection":
   IC analysis, L, S-curve, accent, accidence, affix, affixation,
   allomorph, angle, apex, articulation, bend, bending, bifurcation,
   bight, bound morpheme, bow, bowing, cant, chevron, coin,
   conflexure, conjugation, corner, crank, crook, crotchet, cutting,
   declension, deflection, derivation, difference of form, dogleg,
   elbow, ell, enclitic, enunciation, flection, flex, flexure, fork,
   formative, free form, furcation, geanticline, geosyncline,
   hairpin turn, hook, immediate constituent analysis, infix,
   infixation, intonation, intonation pattern, knee, meander,
   modulation, morph, morpheme, morphemic analysis, morphemics,
   morphology, morphophonemics, nook, oxbow, paradigm, pitch,
   pitch accent, point, prefix, prefixation, proclitic, pronunciation,
   quoin, radical, reflection, root, speech tune, stem, suffix,
   suffixation, suprasegmental, sweep, swerve, theme, timbre,
   tonality, tone, tone of voice, turn, turning, veer, vertex,
   word-formation, zag, zig, zigzag