It's fashionable nowadays to rail against the hateful, offensive, blasphemous word "accompanist." "Collaborative pianist"or just "pianist" tend to be accepted as more PC, more considerate, more elegant.
My opinion: nope.
I like the word "accompanist." Why? Because when I with you up on that stage, OK, yes, we're collaborating. But I am not following you. If I were, I would already have to be behind you. I am accompanying you. To accompany is to go with, to remain with, to stay with. If I am your accompanist, you can trust me. You can trust that I am by your side and sticking with you, from capo to fine. My favorite aspect of accompanying, the reason I still do it, is that bond of utter trust between my soloist and myself. In a sense, we have to accompany each other.
That is why I am proud to be an accompanist.