欠乏
けつぼう · ketsubou · JLPT N1 · noun
deficit
欠 = lack, 乏 = scarce: a lack that runs scarce, so shortage
欠 (ketsu) means to owe or be missing; 乏 (bou) means scarce or lacking. Combined, they mean a shortage of something needed.
欠 — person 人 below + open mouth 欠 top (yawning figure)
Pictograph of a person kneeling with mouth wide open, exhaling — originally depicting a yawn or breath. From this came meanings like 'to lack' or 'to owe', as if something is missing or breathed out. It now serves as a radical in characters related to breathing, singing, or desire (歌, 歡, 欲).