tuba

UK: /ˈtjuːbə/ US: /ˈtubə, ˈtju-/ ,(to̅o̅′bə, tyo̅o̅′-)

Inflections of 'tuba' (n):

tubas

npl

tubae

npl (Rare)

WordReference Random House Learner's Dictionary of American English © 2025

tu•ba /ˈtubə, ˈtyu-/   n. [countable] , pl. -bas. 

1. Music and Dance a brass musical wind instrument with valves, having a low range.

WordReference Random House Unabridged Dictionary of American English © 2025

tu•ba  (to̅o̅′bə, tyo̅o̅′-), n., pl. -bas for 1a, b, 2; -bae (-bē) for 1c.

1. [Music.]
   • a valved, brass wind instrument having a low range.
   • an organ reed stop of large scale with tones of exceptional power.
   • an ancient Roman trumpet.
2. Meteorology See funnel cloud. 

• Latin: trumpet; akin to tube
• 1850–55

Collins Concise English Dictionary © HarperCollins Publishers::

tuba / ˈtjuːbə/ noun ( -bas, -bae / -biː/)

1. Also called: bass horn a valved brass instrument of bass pitch, in which the bell points upwards and the mouthpiece projects at right angles. The tube is of conical bore and the mouthpiece cup-shaped
2. a powerful reed stop on an organ

Etymology: Latin