Background
I'm an intern at a corporation (3/10 months in), and work directly for the manager of the department (I.T.). I do good work and my boss definitely likes (tolerates) me.. I'm nearing 30 years old, and most everyone else is 40+ years old..
There's one man in particular who also works directly for the manager (maybe 45-48 y.o.), let's call him "John", and he's been working here for 3-4 years. He's sometimes goofy and loud, slightly temperamental, and seems to like making (lame/forced/just not funny) jokes at inappropriate times (nothing sexual). When this happens I try to read my boss's face/body language, and I can tell he doesn't like it. Other than that though, I suppose John does good work and "gets things done".
The relationship between me and John is as follows:
We work in adjacent cubicles, and interact 2-3 times a day. When we interact it feels a little forced, mostly because I think the guy is obnoxious, and he tries to explain everything all the time, assuming nobody knows anything. I have a very technical background, whereas he doesn't so much, and so, many of our interactions are him explaining something to me that I already know, and me pretending that I'm listening and learning. This is why I say its "forced", in some respect.
We sometimes will have conversations about non work related things, and every other week on payday we (the department) get breakfast together before work. During those times things are a bit "smoother", but he still makes inappropriate remarks and maintains that demeanor outside of the workplace. Because of that, I choose not to engage too much with him. So, our relationship is definitely more "business" than not.
End Background
So, today we're all in a meeting (me, my boss and John), and John is talking about how a bunch of people won't be in the office tomorrow, including my boss, and in response to John's statements I said, "Yeah, it'll just be me and you, buddy". I didn't emphasize the "buddy" or anything; it just was a light-hearted, quick remark. And I don't think it phased either of them, per se, however, nobody said anything in response (though, what would they say anyway?).
Question:
Even though I don't work for John, he does have seniority over me, and given the fact that the comment was light-hearted, was it rude that I called him "buddy"? How did our boss interpret this? And how might you have reacted if you were John?