What does deluge mean? deluge. Noun 1. A great flood or rain. For example, The deluge continued for hours, drenching the land and slowing traffic to a halt. 2. An overwhelming amount of something; anything that overwhelms or causes great destruction. For example, The rock concert was a deluge of sound. 3. (Military engineering) ; A damage control system on navy warships which is activated by excessive temperature within the Vertical Launching System. deluge. Verb 1. (transitive) ; To flood with water. 2. (transitive) ; To overwhelm. For example, After the announcement, they were deluged with requests for more information.