The crossword solution for the term 'fulminate (against)' is RAIL. The term fulminate means to express vehement protest or censure, and is often used in the context of a person or group expressing strong disapproval of something. The word RAIL is derived from the Latin word 'raille' which means to scold or rebuke. Therefore, the crossword solution for the term 'fulminate (against)' is RAIL, which is an appropriate word to describe the act of expressing vehement protest or censure.