Aside from the 4 safety rules of gun handling, one of the first things a person learns, or should learn concerning firearms is the common nomenclature. I have yet to find an instructor that uses improper words to describe specific parts on a firearm.
There's a reason for this: All parts have a specific name! A clip is different from a magazine and the terms are by no means interchangeable.
Even though that is true, there are still myriads of shooters using incorrect terminology when referring to specific parts of the weapon. And truly, when I see someone make a post referring to a "clip" instead of a magazine, it serves as a mental note to me that the person is either [a] ignorant of the part name [b] really thinks that a magazine is a clip, or [c] doesn't give a rat's hind end either way.
Most unfortunate is that some organizations that should know better interchange the two.
The common defense for using the term clip instead of magazine is, "well everyone knows what was meant". Really? If you need a set of tires, go to the tire store and tell the guy behind the counter that you need four new wheels and that you'll be back later to pick the vehicle up. He knew what you meant, right?
Is this a pet peave of mine? You bet. When I see someone incorrectly use the term it makes me think that they fall into one of the ABC categories above, and it instantly marks them in my mind as a newb ... no matter how long they claim to be a shooter. And really, if they have been shooting for a long period of time and still call a mag a clip, it only solidifies in my mind that they have had no professional training and I will interact with them accordingly or not at all.
Learn and use the proper nomenclature!