hydrostatic lock

(mechanical engineering, usually uncountable) A condition that arises when a device which compresses gases seizes up because of the infiltration of liquid, which prevents further compression.

(countable) A lock for raising and lowering boats on a canal or waterway that operates by using pressurized water to flood or drain the level inside the lock.

(countable) A locking mechanism that uses hydrostatic pressure in order to achieve a seal.