1. Highly critical or judgmental.
2. Of, pertaining to, or designating a fluid at a temperature and pressure greater than its critical temperature and pressure.

Water normally boils as temperature rises, but if both pressure and temperature push up beyond a certain critical point, the gas and liquid phases merge into a supercritical fluid that is denser than steam but lighter than liquid water

Supercritical water is especially effective at leaching metals and other nutrients out of rock. Some, such as sulphur, provide energy for the organisms that live around vents, which have no light to start a food chain; also iron is essential for the growth of plankton.