You were supposed to die, but you didn't. Maybe even got out of it intentionally. Like in the Final Destination movies, one of the characters has a premonition of a disaster that's going to happen, so he avoids the disaster which should've killed him. He cheated death.
It means the person was in a circumstance that often results in death, but did not die.
Like they were in a wicked head-on car crash, or fell off a cliff, or something like that.
Cheated death means you prevented yourself from dying. For instance, some people get cancer which is pretty much a death sentence, but with chemotherapy and other things you can be rid of some cancers. It is mostly a saying. Basically, coming close to death and then recovering in a miracle kind of way is considered "cheating death".
cheating death means that you should have died, but didnt. example, a piano falls off a roof and you were an inch away from getting hit. all odds say that you should have been hit and died, but you were lucky enough to miss it.
it means it was ur time to die but somehow you didnt so you cheated death.
or its like...a point where your about to die but a miracle happened and you didnt, so you cheated death.