proofed proo·fed UK/pɹuːft/ US/ˈpruft/ uncommon adjective 1. treated so as to become resistant “rust-proofed automobiles” “shrink-proofed fabrics” Similartreated WordNet 2.1 (Princeton University). Wiktionary (CC BY-SA). CMU Pronouncing Dictionary. WordNet 2.1 Copyright Princeton University. All rights reserved.