Thanks for all informative responses.

This is a US based travel agent and I don't think it has anything to do with translation. I found it strange that they list different descriptions for identical situations and never seen new terminology used before this booking and hence coming here for an answer.

I reached out to my TA and this is the answer - For the segments that read “Meal at Cost”, means you can pre order a meal via the Exec Plat desk, it is still for purchase, but you can order in advance to be sure you get what you want.

This still doesn't make any sense to me. If I'm flying in economy as EXP I would get complimentary drink & snack (sandwich) and doubt that there is a way to pre-order this type of meal since its standard snacks and one choice of sandwich based on time / route. If I'm flying in first (there is no business on these short flights) I would assume I can pre-order hot meal that is included but I have the ability to pre-select it since there are few choices. I guess I'll call AA EXP to find out what it really means if anything at all.