tone 
(tōn)
(tōn)n.
1. Music
a. A sound of distinct pitch, quality, and duration; a note.
b. The interval of a major second in the diatonic scale; a whole step.
c. A recitational melody in a Gregorian chant.
2.
a. The quality or character of sound.
b. The characteristic quality or timbre of a particular instrument or voice.
3.
a. The pitch of a word used to determine its meaning or to distinguish differences in meaning.
b. The particular or relative pitch of a word, phrase, or sentence.
4. Manner of expression in speech or writing: took an angry tone with the reporters.
5. A general quality, effect, or atmosphere: a room with an elegant tone.
6.
a. A color or shade of color: light tones of blue.
b. Quality of color: The green wallpaper had a particularly somber tone.
7. The general effect in painting of light, color, and shade.
8. Physiology
a. The normal state of elastic tension or partial contraction in resting muscles.
b. Normal firmness of a tissue or an organ.
v. toned, ton·ing, tones
v.tr.
1. To give a particular tone or inflection to.
2. To soften or change the color of (a painting or photographic negative, for example).
3. To sound monotonously; intone.
4. To make firmer or stronger. Often used with up: exercises that tone up the body.
v.intr.
Phrasal Verb: 1. To assume a particular color quality.
2. To harmonize in color.
tone down
To make less vivid, harsh, or violent; moderate.
[Middle English ton, from Old French, from Latin tonus, from Greek tonos, string, a stretching; see ten- in the Appendix of Indo-European roots.]