Context is Everything.

A while ago I was at an evening do and was chatting to this bloke who, when not boring people shitless in his leisure time, was obviously some kind of hyper-professional shark. He had this really irritating habit of conversational oneupmanship where for example, if you mentioned that you drove an Audi, he'd immediately cut in and tell you that he drove a Merc. It reminded me a lot of the school playground and the old "my-daddy's-bigger-than-your-daddy" debate.

It then struck me that there are many, many positive words for people who are competitive within a competitive context (i.e. sport, work etc.): Ambitious, driven, aspiring, energetic, keen, enterprising, go-getter and so on.

But strangely there is only one word for a person who is competitive in a non-competitive context: Dick.