The Full Form of BLEVE is Boiling liquid expanding vapor explosion.

A boiling liquid expanding vapor explosion (BLEVE, /ˈblɛviː/ BLEV-ee) is an explosion caused by the rupture of a vessel containing a pressurized liquid that has reached temperatures above its boiling point.Because the boiling point of a liquid rises with pressure, the contents of the pressurized vessel can remain liquid so long as the vessel is intact. If the vessel’s integrity is compromised, the loss of pressure and dropping boiling point can cause the liquid to rapidly convert to gas and expand extremely rapidly. If the gas is combustible as well, as is the case e.g. with hydrocarbons and alcohols, further damage can be caused by an ensuing fire.