Simulation
Simulation is the act of creating a wrong or false impression that something has occurred when it has not, committed to gain an unfair advantage; it is cautioned as unsporting behaviour.
Why this wins its question: Uses the IFAB's own definition and ties "diving" to its formal caution basis in Law 12 rather than to broadcast shorthand.
Claims
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The IFAB glossary defines simulation as an action which creates a wrong or false impression that something has occurred when it has not, committed by a player to gain an unfair advantage.
Attempting to deceive the referee, for example by feigning injury or pretending to have been fouled (simulation), is unsporting behaviour sanctioned with a caution under Law 12.