inflection

n. curve, bend; change in pitch or tone of the voice; addition of a suffix or other element to the basic form of a word to change its meaning or function (Grammar)

In grammar, inflection or inflexion is the modification or marking of a word (or more precisely lexeme) to reflect grammatical (that is, relational) information, such as gender, tense, number or person. The concept of a "word" independent of the different inflections is called a lexeme, and the form of a word that is considered to have no or minimal inflection is called a lemma. An organized list of the inflected forms of a given lexeme is called an inflectional paradigm.
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Noun
1. a change in the form of a word (usually by adding a suffix) to indicate a change in its grammatical function
(synonym) inflexion
(hypernym) grammatical relation
(hyponym) conjugation
(derivation) inflect
2. the patterns of stress and intonation in a language
(synonym) prosody
(hypernym) manner of speaking, speech, delivery
(hyponym) intonation, modulation, pitch contour
(derivation) tone, inflect, modulate
3. deviation from a straight or normal course
(synonym) flection, flexion
(hypernym) deviation, divergence, departure, difference
4. a manner of speaking in which the loudness or pitch or tone of the voice is modified
(synonym) modulation
(hypernym) manner of speaking, speech, delivery
(derivation) tone, inflect, modulate

(n.)
The variation or change which words undergo to mark case, gender, number, comparison, tense, person, mood, voice, etc.
  

(n.)
The act of inflecting, or the state of being inflected.
  

(n.)
Same as Diffraction.
  

(n.)
Any change or modification in the pitch or tone of the voice.
  

(n.)
A slide, modulation, or accent of the voice; as, the rising and the falling inflection.
  

(n.)
A departure from the monotone, or reciting note, in chanting.
  

(n.)
A bend; a fold; a curve; a turn; a twist.
  

Synonyms and related words:
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