There was a young fellow from Tring
Who said when they asked him to sing
'You may think that it's odd
But I cannot tell God
Save the Weasel from Pop goes the King'

If you can tell one tune from another, then you are not tone deaf. Very few people are. (Allegedly, King Edward VII was. He is said to have been able to recognise only two tunes - the national anthem and 'the other one'. The national anthem was the one people stood up for.)

If you can't sing a tune accurately, you are not tone deaf, just vocally challenged. A lot of people have this problem, but with the right kind of help, and a bit of effort, most of them can learn how to sing acceptably.

Unfortunately, some music teachers don't see it this way. Because singing came naturally to them, they can't understand why some people have problems getting it right. It saves these teachers a lot of trouble to write off students who have difficulty hitting notes accurately as "tone deaf" - as well as leaving them more time to get on with coaching the choir.

This strategy has produced some good choirs, but it has also let down a lot of students who might have gained great enjoyment from music, if only they hadn't been told at an impressionable age that they were 'tone deaf'.

Wassail!