LYSIS Meaning of LYSIS in English [ 'lʌɪsɪs ]■ noun Biology the disintegration of a cell by rupture of the cell wall or membrane.OriginC19: from L., from Gk lusis 'loosening', from luein 'loosen'. Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004