whacking
adjective
British, informal
we weren't prepared to pay a whacking salary:
huge, massive, enormous, gigantic, very big, very large, great, giant, colossal, mammoth, vast, immense, tremendous, mighty, stupendous, monumental, epic, prodigious, mountainous, monstrous, titanic, towering, elephantine, king-sized, king-size, gargantuan, Herculean, Brobdingnagian, substantial, extensive, hefty, bulky, weighty, heavy, gross;
informal mega, monster, whopping, whopping great, thumping, thumping great, humongous, jumbo, hulking, bumper, astronomical, astronomic;
British, informal whacking great, ginormous.
whacking Oxford Dictionary of English