Simple past tense and past participle of swarm.(verb)
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Use "swarmed" in a sentence
"His faith in Kerry was not misplaced and he finally located the "rebellion", such as it was when a small band of men swarmed from a doorway and dragged him into a dimly lit room."
"Then in swarmed the Hun and, for a period, street fighting was going good."
"The three islanders swarmed from the tiny forecastle, two of them leaping to the halyards and holding by a single turn, while the third fastened down the engineroom, companion and swung the ventilators around."