"Tit for tat" means giving back to someone exactly what they have given to you, especially in retaliation for something harmful or unpleasant. It implies a kind of equivalent retaliation or "an eye for an eye" response, where one party responds with the same action that was done to them, often used in the context of retaliation or punishment to restore balance.
The phrase originally comes from "tip for tap," meaning "blow for blow," and is used commonly to describe behavior where if someone does something bad to another person, the latter gives back the same kind of bad response. It is typically used for petty or small retaliations rather than serious conflicts.
In addition, "tit for tat" is also the name of a well-known strategy in game theory where a player in an iterated game cooperates on the first move and then mimics the other player’s previous move in subsequent rounds.
In sum, "tit for tat" means responding to an action with an equivalent action, especially in retaliation or punishment.
