Someone else cheating on a test, on taxes, in a deal, in a game, etc. can mean:
The idea of unethical shortcuts, dishonesty, or stealing is on your mind, possibly because of a situation in real life
You resent someone whom you feel is attempting to control you (teacher, government, other authority), and you are rebelling because you feel unempowered
You cheating can mean:
You honestly don't want to do the work or you'd prefer a shortcut somewhere in your life
You are are dreading or not interested in something you have to do
You're feeling dishonest or are considering cheating or its consequences
Possible dream symbol meanings in the dream dictionary are suggested. No "standard meanings" exist because dream meaning is subjective and specific to the dreamer.