When pronounced "base"--
1: Guitar-like stringed instrument used in bands and orchestras.
2: The ever-popular bass guitar, which is used by many smaller bands.
3: Any other instrument or item that emits low-pitched, rumbling sounds. Ex.: A bass trombone, bass-boost speaker system, and so on.
4: The lowest voice division in choir, hopefully composed of males. Basses aren't always able to sing something worthy of Barry White but they're typically on the lower end of the voice spectrum.
When pronounced "bass"--
A common type of fish; sometimes "bass" is used to refer to a single species of this type, ex.: largemouth bass.
1: Johnny plays the bass in the orchestra.
2: Dude, that garage band has THE best bass player I've ever seen.
3: That speaker system is tight! I love that rumblin' bass line, man.
4: I am a Bass in the church choir.
1: 'Ey, Joe, let's go bass fishing. My wife is being an evil bitch.
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