DECUMBENT Meaning of DECUMBENT in English [ dɪ'kʌmb(ə)nt ]■ adjective Botany (of a plant stem) lying along the ground, with the extremity upturned.OriginC18: from L. ~- , decumbere 'lie down'. Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004