NO it is NOT ok.
ACEO is a size - 2.5x3.5" only - if what you are offering is not ACEO related. Don't use it, you are 'shooting yourself in the foot', and really doing the whole ACEO art movement a disservice.
If I see someone using it, look at the listing and it's not an ACEO, I never look at that person's work again, quite frankly. It's like ... once bitten, twice shy.
It also is keyword spamming/mis-leading titles. I know that that can be argued, but being associated with ACEOs some 19 months now, I have seen some very sad people when their listings got pulled as someone had reported them on the basis of those ebay standards in the past.
Please - only use ACEO if you are offering ACEOs/ACEO related.
There was a time that people were emailed and nicely asked to remove ACEO from titles, explaining that ACEO is size only, but I'm not aware of anyone doing that currently.
Thanks for raising this question.
~Jillian
~Jillian
artist, Jillian Crider
... google me!