song

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Music A brief composition written or adapted for singing.
2. n. Music The act or art of singing: broke into song.
3. n. A distinctive or characteristic sound made by an animal, such as a bird or an insect.
4. n. Poetry; verse.
5. n. A lyric poem or ballad.
6. idiom. for a song Informal At a low price: bought the antique tray for a song.

Century Dictionary and Cyclopedia

1. n. Singing; vocal music in general; utterance in tones of musical quality and succession, with or without words: opposed to speech and to instrumental music.
2. n. The musical cry of some birds (see singing bird, under sing) and, by extension, of some other animals.
3. n. A short poem intended for singing, or set to music; a ballad or lyric. A song is properly distinguished by brevity, free use of rhythmic accent and rime, more or less division into stanzas or strophes, often with a refrain or burden, comparative directness and simplicity of sentiment, and a decidedly lyrical manner throughout.
4. n. A particular melody or musical setting for such a poem, for either one or several voices (in the latter case usually called a part-song or glee). Songs are generally written in song form, but are often irregular also. They usually contain but a single movement, and have an accompaniment of a varying amount of elaboration. They are classified as folk-songs, which spring up more or less unconsciously among the common people, or art-songs, which are deliberately composed by musicians (see lied); as strophic, when made up of a movement repeated for the several strophes, or composed through, when the music varies with the successive strophes; or they are named by reference to their general subject or style, as rustic, patriotic, national, martial, naval, nuptial, hunting, bacchanalian, etc.
5. n. Poetry; poetical composition; verse.
6. n. A more trifle; something of little or no value: as, I bought it for a song.
7. n. A Middle English preterit of sing.

Wiktionary

1. n. A musical composition with lyrics for voice or voices, performed by singing.
2. n. by extension any musical composition
3. n. The act or art of singing.
4. n. A melodious sound made by a bird, insect, whale or other animal.
5. n. Something that cost only a little; chiefly in for a song.

GNU Webster's 1913

1. n. That which is sung or uttered with musical modulations of the voice, whether of a human being or of a bird, insect, etc.
2. n. A lyrical poem adapted to vocal music; a ballad.
3. n. More generally, any poetical strain; a poem.
4. n. Poetical composition; poetry; verse.
5. n. An object of derision; a laughingstock.
6. n. A trifle; an insignificant sum of money.

WordNet 3.0

1. n. a distinctive or characteristic sound
2. n. a very small sum
3. n. the act of singing
4. n. a short musical composition with words
5. n. the imperial dynasty of China from 960 to 1279; noted for art and literature and philosophy
6. n. the characteristic sound produced by a bird