So what you are sayin there Bobster, is that Webster's is wrong , and you are so right that it is unchallengeable? Wow!
If you want to cut singers out of the herd so to speak, by saying they are not musicians, but vocalist, then we would have to call instrument players instrumentalist, right?! That is according to your principles of the definition of the work musician.
Once again: Musician Mu*si"cian, n. [F. musicien.]
One skilled in the art or science of music; esp., a skilled
singer, or performer on a musical instrument.
Merrian's Webster dictionary: mu·si·cian Listen to audio/mjuˈzɪʃən/ noun
[count] : a person who writes, sings, or plays music
- definition noun [countable] British English pronunciation: musician /mjuˈzɪʃ(ə)n/
musician plural musicians
1. someone who performs or writes music, especially as their job
Okay Bob, your right I give up, and you win.
That's a D chord after the G?