Simple past tense and past participle of understock.(verb)
Insufficiently stocked(adjective)
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Use "understocked" in a sentence
"Cluttered or understocked shelves reflected an inventory problem; 4."
"Our kids' friends used to criticize them for living in a house with an understocked refrigerator."
"Here in South Africa things are far from perfect, our community clinics in informal settlements often overburdened with patients, understaffed and understocked with life-saving medical supplies, and people often have to queue for more than a day only to get turned away at the last minute."