Belonging to, or like, the family of plants of which the prickly pear is a common example.(adjective)
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Use "cactaceous" in a sentence
"Fertile soils and spontaneous vegetation, reeking with miasma and overpowering from their odour, we had exchanged for a drouthy wilderness of aloetic and cactaceous plants, where the kolquall and several thorn bushes grew paramount."