swarm

nouns

a moving crowd
drove, horde, swarm
a group of many things in the air or on the ground
"a swarm of insects obscured the light"; "clouds of blossoms"; "it discharged a cloud of spores"
cloud, swarm

verbs

be teeming, be abuzz
"The garden was swarming with bees"; "The plaza is teeming with undercover policemen"; "her mind pullulated with worries"
pullulate, swarm, teem
move in large numbers
"people were pouring out of the theater"; "beggars pullulated in the plaza"
pour, pullulate, stream, swarm, teem