Learner Proper usage?

An associate of mine has been using the word learner when referring to trainees. This keeps bugging me as it doesn't quite sound right and I have a hard time using the word myself. Maybe I am just used to the word trainee but is this the correct word to use to refer to a trainee.

[MrPedantic]

Hello S8

You might say that a "learner" is someone who is acquiring a skill or a kind of knowledge (i.e. how to do something, e.g. drive a car); while a "trainee" is someone who is acquiring the skills necessary for a particular job (i.e. how to be something, e.g. a plumber).

But since, by and large, a trainee needs to be a learner too, it might be difficult to object to the usage; except on the grounds that it seems a little undignified.

Other members may have other views, though!

Have a good Monday,

MrP