A more thorough explanation:

Definition: Pro tanto is a Latin phrase that means "to that extent" or "for so much." It is often used to refer to a partial satisfaction of a debt or claim.

Example: In a lawsuit where there are multiple defendants, a plaintiff may settle with one of the defendants and then pursue further action against the remaining defendants. This settlement is called a "pro tanto settlement." The remaining defendants are entitled to offset the pro tanto settlement against any judgment entered against them. For instance, if a plaintiff settles with one defendant for $10,000 and then wins a $50,000 judgment against the other defendant, the judgment will be reduced to $40,000.

Another example of pro tanto is in a personal injury case where the plaintiff settles with the defendant for a certain amount of money. The settlement is considered a partial satisfaction of the plaintiff's claim, and the plaintiff can still pursue further action against other defendants who may be responsible for the injury.

The examples illustrate that pro tanto refers to a partial satisfaction of a debt or claim. It is used in legal cases where there are multiple defendants, and one defendant settles with the plaintiff. The settlement amount is then used to offset any judgment entered against the remaining defendants. Pro tanto settlements are common in personal injury cases where there may be multiple parties responsible for the injury.