The Oxford Thesaurus An A-Z Dictionary of Synonyms - overwhelm v.

1) overpower, overcome, overtax, devastate, stagger, crush, defeat, destroy, subdue, suppress, quash, quell, conquer, beat, bring down, prostrate, weigh down, oppress: Overwhelmed by grief, she dissolved into tears. 2) inundate, overcome, engulf, submerge, flood (over) ; deluge, swamp, bury, immerse: A feeling of terror suddenly overwhelmed me as I watched my safety rope fray and break. In only a few hours the rising waters had completely overwhelmed the house. 3) overcome, stagger, astound, astonish, dumbfound or dumfound, shock, stun, bewilder, confuse, confound, nonplus, surprise, take aback, Colloq bowl over, knock off one's feet or pins, blow one's mind, discombobulate, Brit knock for six: We were overwhelmed by the friendly reception that awaited our return.