"ad" isn't an abbreviation here. It is Latin and means as much as "to" or "until". So "ad infinitum" means something like "until infinity" or "neverending".
If it's a Latin word it means 'to'. If you mean the abbreviation, the full form is 'advertisment'.
Depending on context, AD may mean admitting diagnosis, advanced directive, after discharge, Alzheimer's disease, or right ear.Advance DirectiveAlzheimer's disease
ad
If you mean, what is a common abbreviation used for "advertisement," then I would assume you're thinking of "ad." As in, "Did you see my ad in the newspaper for a babysitter?"
Anno Domini ("year of the lord") is abbreviated with AD. It is the same AD you will see in years such as 2014 AD, which means the 2014th year after Jesus was born. The opposite of this is BC, which is an abbreviation for "Before Christ"
It is an abbreviation for advertisement.
Yes. It is ad.
ad lib is a latin abbreviation for 'freely'
ad-ho: Advanced Developers Hands-On Conference
In the year of our lord
It should be capitalized when it's an abbreviation.