treble

from The American Heritage® Dictionary of the English Language, 5th Edition.

• adjective Triple.
• adjective Music Relating to or having the highest part, voice, or range.
• adjective High-pitched; shrill.
• noun The highest part, voice, instrument, or range.
• noun A singer or player that performs this part.
• noun A high, shrill sound or voice.
• transitive & intransitive verb To make or become triple.

from The Century Dictionary.

• Threefold; triple.
• In music, pertaining to the voice or the voice-part called treble or soprano; high in pitch; in harmony, occupying the upper place: as, a treble voice; a treble violin. See II.
• noun In music: Same as soprano (which see).
• noun A singer with a soprano or treble voice, or an instrument that takes the upper part in concerted music.
• noun Also triplex.
• noun In short whist, a game which counts three points to the winners, their adversaries not having scored.
• To make thrice as much; make threefold; multiply by three; triple.
• To utter in a high or treble tone; hence, to whine.
• To become threefold.

from the GNU version of the Collaborative International Dictionary of English.

• adverb obsolete Trebly; triply.
• adjective Threefold; triple.
• adjective Acute; sharp.
• adjective Playing or singing the highest part or most acute sounds; playing or singing the treble.
• noun (Mus.) The highest of the four principal parts in music; the part usually sung by boys or women; soprano.
• intransitive verb To become threefold.
• transitive verb To make thrice as much; to make threefold.
• transitive verb obsolete To utter in a treble key; to whine.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• adjective Threefold, triple.
• adjective music Pertaining to the highest singing voice or part in harmonized music; soprano.
• adjective High in pitch; shrill.
• noun music The highest singing voice (especially as for a boy) or part in musical composition.
• noun music A person or instrument having a treble voice or pitch; a boy soprano.
• noun Any high-pitched or shrill voice or sound.
• noun A threefold quantity or number; something having three parts or having been tripled.
• noun darts Any of the narrow areas enclosed by the two central circles on a dartboard, worth three times the usual value of the segment.
• noun sports Three victories, awards etc.
• verb transitive To multiply by three; to make into three parts, layers, or thrice the amount.
• verb intransitive To make a shrill or high-pitched noise.
• verb intransitive To become multiplied by three or increased threefold.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• adjective three times as great or many
• verb sing treble
• adjective having more than one decidedly dissimilar aspects or qualities
• adjective having three units or components or elements
• verb increase threefold
• noun the pitch range of the highest female voice
• adjective having or denoting a high range