PERIDIUM Meaning of PERIDIUM in English [ pɪ'rɪdɪəm ]■ noun ( plural peridia -dɪə ) Botany the outer skin of a sporangium or other fruiting body of a fungus.OriginC19: from Gk pēridion , lit. 'small wallet'. Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004