inflection

INFLEC'TION, n. [L. inflectio.] The act of bending or turning from a direct line or course.

1. In optics,a property of light by which its rays, when they approach a body, are bent towards it or from it.

2. In grammar, the variation of nouns, &c., by declension, and verbs by conjugation.

3. Modulation of the voice in speaking.

More commonly inflection gives significance to tones.

Point of inflection, in geometry, the point where a curve begins to bend the contrary way.