What is Muso?
1.
A musician who uses 12 chords where 3 will suffice.
Why do Rush have to include so many deeply unnecessary chord changes in their songs? Man, what a bunch of total musos.
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2.
Someone who is obsessed with listening to and creating
guy1: Look at this guy! He plays guitar, piano, AND has professional singing lessons!
guy2: Yeah, he's a real muso.
See