Nineteen Marines

So we're driving along.

Garrett: Were there nineteen ____________ marines?
Me: (Thinking that it really sounds like he just asked me if there were nineteen pissed off marines but knowing that my son doesn't say stuff like that) Nineteen what, Buddy?
Garrett: Nineteen marines.
Troy: What did you say before?
Garrett: What do you mean?
Troy: Nineteen what kind of marines?
Garrett: (hesitating) Um. I don't remember.
Me: You said nineteen some kind of marines. What did you say?
Garrett: Oh. Nineteen pissed off marines. (He says completely nonchalant.)
Me: Where did you hear that?
Garrett: It was on a show.
Me: Okay. Usually we don't say that.
Garrett: Oh.
Me: There are really naughty words and then there are kind of naughty words and that's a kind of naughty word and you shouldn't say it.
Garrett: Okay. (Pause) What does it mean?
Troy & Me: (At the same time) Really mad.
Garrett: Okay...so were there nineteen really mad marines?
Troy: Well, I don't know. If the show said there were, there probably were.