One theory suggests that the origin of the term was "keep cavey", from the Latin verb caveo, which means "look out for"; this phrase was used by Jews living in East London between the two wars.Many US promoters and wrestlers at that time were of Eastern European origin and many had heavy accents, leading to the term being transformed into "kayfabe".Heels are villainous or antagonistic characters, whose personalities are crafted to elicit a negative response from the audience.
Every time he did, someone would yell "Kayfabe." ...
Also, since wrestling is performed in front of a live audience, whose interaction with the show is crucial to its success, kayfabe can be compared to the fourth wall in acting, since hardly any conventional fourth wall exists to begin with.
In general, anything in a professional wrestling show is to some extent scripted, or "kayfabe", even though at times it is portrayed as legitimate.
Another term for "kayfabe" is the word "work", or "worked", which also refers to the staged nature of professional wrestling.
In contrast, something that is not "kayfabe" but legitimate, be it a fight or a statement, is referred to as a "shoot".