Definitions are, by definition (), to be exact rather than simple.
I'd totally disagree... in a way! Take "attractiveness" in humans for example. It's very wide in range and in no way, specific! Some ppl would find one girl/guy attractive while the others don't. The definition is very specific in the case that it accurately shows that attractiveness is NOT exacting in nature.
So yes definitions are exact, but can represent something that is not exact at all!
The reason I'm saying not to overcomplicate it is because if you're talking about groundspeed of an aircraft, it's that damn simple! It's kind of stupid to bring it up on a forum like this because all the little nerdy/geniuses of this board LOVE to pick apart the simplest definition and make it the most complicated, and then in the end they find they've gotten nowhere! Believe me I like picking apart stuff too (partly the reason I joined), but I think groundspeed should be left alone!