To look on and offer unwanted, usually meddlesome advice to others.
However the common meaning of kibitzing is a person who is being extremely lazy and generally not doing what they should be. kibitzing can sometimes be determined by the way someone is sitting/laying. If they are being more visually lazy in their stature than usual. they can be labelled a "kibitzer" or as "kibitzing".
People who go to bed early at parties or in social spaces can be referred to as "kibitzers" if they are only going home to be lazy and do nothing.
can sometimes be shortened to "bitzing"
if you are a homosexual and are kibitzing you can be referred to as a "Kibender" the amalgamation of the word "Kibitz" and "bender"
Paul: "Rob why are you kibitzing"
Rob: "I'm really tired man"
Paul: "Quit kibitzing"
Glenn: "Rob get out of bed, Quit Kibitzing"
Rob "fuck off man, I'm knackered"
Paul: "look at that absolute kibitz"
Rob: "shut up, i'm well comfortable"