"Mum fancies him," said Fred, in a very audible whisper.
- speaking of Gilderoy Lockhart (CS3)
"I fancied a walk."
- Ron (OP13)
Depends on context. As a verb, this can mean ‘want’ or ‘like’ (usually when referring to things or actions), but when referring to people, indicates romantic attachment (think ‘footloose and fancy-free’). As a noun, a ‘fancy’ is a kind of small cake.