tuba

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A large, valved, brass wind instrument with a bass pitch.
2. n. A reed stop in an organ, having eight-foot pitch.

Century Dictionary and Cyclopedia

1. n. An ancient Roman trumpet with a straight tube of metal, like the Greek salpinx.
2. n. In the Philippine Islands, Guam, and the west coast of Mexico, the sap obtained from the immature inflorescence of the coconut, which is allowed to ferment and is used as a beverage, and from which a distilled liquor called vino, or aguardiente, is obtained.
3. n. In the peninsula of Malacca and the Malay Archipelago, a name applied to a number of fish-intoxicants, especially to Deguelia elliptica, and in the Philippine Islands to Croton Tiglium, Jatropha Curcas, and Cocculus Cocculus, used for the same purpose.
4. n. A musical instrument of the trumpet family, of very large size and low pitch. It is essentially similar to the bombardon, though not always made in the same shape. Its compass is nearly four octaves, including, by means of three or five valves, all the chromatic tones. The fundamental tone is usually the third F or Eþ below middle C. Lower varieties are often called bass or contra-bass tubas. The tuba is much used in military bands, and is more or less common in the orchestra, where it is used in conjunction with the trombones.
5. n. In organ-building, a reed-stop of large scale, so connected with a separate bellows with extra weights that the tones are of exceptional power and majesty. Usually called tuba mirabilis.
6. n. In anatomy and zoül, a tube or tubular part or organ; specifically, the Eustachian tube, or salpinx. See hydra tuba (under hydra), and cut under scyphistoma.

Wiktionary

1. n. A large brass musical instrument, usually in the bass range, played through a vibration of the lips upon the mouthpiece and fingering of the keys.

GNU Webster's 1913

1. n. An ancient trumpet.
2. n. A sax-tuba. See sax-tuba.

WordNet 3.0

1. n. the lowest brass wind instrument