What does T.I.A mean ?

Question

I see it as an abbreviation on the internet all the time. I know it doesn't mean Aunt in Spanish it some slang word

Answer 1

TIA = thanks in advance

It is used when asking a question or a favour. Might well be used here at YA too.

Other similar acronyms for forum discussions and such:
HTH = Hope that helps
IMHO = In my honest/humble opinion
PFMJI = pardon for my jumping in
IIRC = if I remember correctly
OTOH = on the other hand
and so on, you will surely find many lists of them on the net.

Answer 2

This is not slang, but one meaning is Transient Ischemic Attack: T.I.A. It is a mini-stroke, sometimes causing fainting, but leaving little or no detectable damage behind, maybe sometimes a headache. It is a sign of possible clogged arteries to your head, and at least a sign of unstable blood supply to your brain.