What is a synonym for thousand of liter?

There isn't a single, perfect synonym for "thousand liters" because it's a specific measurement. However, here are some options depending on the context:

Formal:

* Kiloliter (kL): This is the standard metric unit for 1000 liters.

* Cubic meter (m³): This is another standard unit, equivalent to 1000 liters.

* One thousand liters: You could simply use the numerical phrase.

Informal:

* Tons: While not directly equivalent, "tons" can be used in some contexts to refer to a large quantity of liquid, though it's less precise than the metric units.

* A large volume/amount: This is a general description that avoids a specific number.

The best synonym will depend on the specific situation and the level of formality required.