Simple past tense and past participle of overcrowd.(verb)
Containing too many occupants for an area of its size.(adjective)
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Use "overcrowded" in a sentence
"For example, if zero tolerance for killing means that we must warehouse animals in overcrowded, disease and pest-ridden cages, and there are not enough staff of volunteers to provide these animals with adequate exercise, aren't we actually torturing these animals for the sake of our own vanity?"
"I can see a possible use for these signs in overcrowded public hunting areas out east to alert people that they are not alone in an area maybe but not in Colorado."
"A refugee advocacy group says displaced Haitians continue to live in overcrowded, unsanitary camps that are plagued by violence -- nine months after a deadly earthquake ravaged the nation."