Literally "He/she plays."
This can be used in the context of playing a game or playing a musical instrument, but the most curious context is in its use as meaning to pretend to be or to mimic - but unconvincingly.
Bezi kyries means that the person accused is playing at being a lady – the implication being that she is doing so unsuccessfully or that such games are inappropriate to the female in question.
Likewise we find Bezi do ballikari, playing the hero, Bezi do yiatro, pretending to be a doctor or bezi don balavos hence pretending to be more stupid than you really are for purposes of gain or avoiding responsibility.
The art to survival in Cyprus is to find people who, for all their limitations, do not seem to feel the need to be bezi-ing at anything.
These are usually the ones who are accused of Bezi-ing o ecsebnos, otherwise known as pretending to be clever.