Pronunciation: (ō"vur-hwelm', -welm'),[key] —v.t. 1. to overcome completely in mind or feeling: overwhelmed by remorse. 2. to overpower or overcome, esp. with superior forces; destroy; crush: Roman troops were overwhelmed by barbarians. 3. to cover or bury beneath a mass of something, as floodwaters, debris, or an avalanche; submerge: Lava from erupting Vesuvius overwhelmed the city of Pompeii. 4. to load, heap, treat, or address with an overpowering or excessive amount of anything: a child overwhelmed with presents; to overwhelm someone with questions. 5. to overthrow.