1. An exclamation most typically used by those exposed to (and not utterly embarrassed by) southern culture. It is, in essence, the southern version of the urban expression 'girl bye'. When spoken sarcastically, it is used to render a thing ridiculous or label it unimportant. When spoken sincerely, it is similar to the expression 'hot dog!' and implies that a thing is impressive, pleasantly surprising, intriguing or a combination of the three.
2. An anatomical orifice used in the act of sex, such as a woman's vagina or a person's anus. The mouth is not typically referred to as a 'boy howdy,' though it, too, fits this description.
Examples include the term 'boy howdy' in snippets of hypothetical conversation, and should be imagined or read aloud in a southern accent.
Boy me & Rick went down to the crick last yesterday and just guess what we saw!
- Now what was that?
We saw us three of THE LOVELIEST creatures bathin' in all god's glory.
-Did you see nipple? It only counts if you saw nipple.
Hell yes we saw nipple.
Golly gee Kyle, me and the boys are heading over to the bowling ally and we're gonna have us a mighty good time! We might even get a little crazy and have a whole dang pitcher of soda, I bet we will. Wanna come?
Condom or nothing, Rick. Make your choice. I don't care if they're not fun, I'll TELL you what's not fun. Growing a whole goddamn person inside you for nine months and then having to push the gaddamn thing out of your boy howdy. I mean it. Condoms or gtfo.