A submission, also called a "tap out" is a combat sports term for yielding to the opponent, resulting in an immediate defeat.
A technical submission or "stoppage" may occur when the referee stops the fight for any reason, including because a fighter has sustained a serious injury like a broken limb or is rendered unconscious.
A submission is either earned when a wrestler taps the mat or their opponent three or more times with their hand, or verbalizes to the referee (often using the phrase "I quit").
Due to pro wrestling's choreographed nature, limbs are not broken as to protect the wrestler in the hold.
To force the breaking of the hold (unless in a match with a no disqualification/no rope-break rule) a wrestler can touch the ring ropes or place part of their body directly under them, the referee will then count to 5, and if the wrestler executing the submission hold does not let go they will be disqualified.