Most loved word:
Perfection Never achievable but we should strive for it nonetheless. This is a quality I look for in developers I work with and especially the ones I hire. If you are driven by the need to do things properly then you're already halfway there.
Most hated word:
Bodge - Otherwise known as a "hack or to "patch up". Resist the urge my friends. Don't succumb to the beautiful songs of the sirens that promise a quick fix. These are the things that, time and time again, return to bite you in most unpleasant ways.
Personally speaking, I'm a pedant, a sceptic, an atheist and a lover of science. Not necessarily in that order.
Oh, and here's one thing I've discovered on my journey in software engineering:
Good developers are not cheap. Cheap developers are not good