mercury fulminate mer·cu·ry·fulminate uncommon noun 1. a fulminate that when dry explodes violently if struck or heated; used in detonators and blasting caps and percussion caps Synonymsmercury fulminatefulminate of mercuryfulminating mercury Related words Broader terms fulminate Parts blasting cappercussion cap WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.