According to Dictionary.com, you are correct.....Butthole [Buht-hohl].....noun...Slang, Vulgar.....1 anus. 2 Stink flower. Well maybe not number 2.

Pothole.

Maybe it depends on how deep it is?    I mean this is some deep shit, right?

ROTFLMAO!

No question!     :)

I don't care for boy pussy because a pussy is most commonly associated with a (ugh) girl even though it is where you fuck a boy. Instead, how about referring to a boy's anal opening as a boy's pucker or his pleasure hole. With either term, there are no negative associations with its primary biological function. 

Interesting!    Fascinating insight!    I will try to keep that in mind as I go through this thing called life.    Do you mind if I share this information with our fellow human beings?     Of course this idea and concept might well be worthwhile to be reminded of ever so often so feel free to bring it up at any point down the line as well, DevinAlexander.     Good job!    :)

It's always asshole just as fishhook is always fishhook. It's still asshole when referring to an open anal sphincter muscle. If you said his ass has a tight hole it may be a bit redundant but it's easier to say, his asshole is tight. Some common slang terms aren't even recognized, like peehole. You would need to say "meatus", which kind of makes sense since we often refer to a guy's penis as "meat". 

American dictionary, American phonetics.

I KNEW that you or someone would pull this shit out of an asshole so that's why I said, "between the two"!     Very predictable!   (Eye roll.    Or is it eyeroll?)      I think it depends on the mood you are in and what impression you wish to make as well as how much of a hurry you are in frankly!    Probably not too much more of a reason to think and or dwell on it otherwise, huh?     I'd love to hear what you all think!     :)      Besides...I have used, "arse", plenty of times if I do say so myself!     :)   

A false dichotomy: you can't justify yourself by presenting two wrong choices without correction by me or anyone else. Roll your eyes all you want - the choice you present is incorrect, especially as you recognise the validity of 'arse'.

Zany, C4LEB has autism. Forgive her for being a pompous asshole. 

AND on top of this and or that while I might and am pretty sure I have heard and probably used the term, "arsehole", very specifically I am not sure how often I have seen it as one word.   I mean MAYBE but let's be honest.    From a statistical anal-ysis it isn't used any where near as often as the other two options.    Let's stay focused Mr. A.D.D. and decide on one of the two options being discussed in such great detail.