Yes it is, as far as I'm concerned---just some people don't like it and say it's incorrect or slang. If I remember right, it was actually used by the quite high-class English back in the 1920s.
It is a word, yes: it's an informal ex<x>pression or colloquialism for "am not", "are not" or "is not". For example: "If it ain't broke, don't fix it". You just shouldn't use it in formal writing.
Yes it is. It just sounds better to say "Ain't that right?" than "Isn't that right?". Same way y'all sounds better than "you all"
No it ain't ain't. It's are not ain't it?
It is indeed a word, but perhaps not a "preferred word" among the socially elite.
umm sorry to disagree, but I believe they added it to the websters dictionary a few years back.
phrase and not a word.
No,it's not a word but "Isn't" is a word "Is Not".
I didn't understand your question. What's "ain't." Is it slang or some foreign world? ;-)
no it ain't