PETA- Meaning of PETA- in English [ 'pɛtə ]■ combining form denoting a factor of 10 15 : petabytes. Originfrom pe(n)ta- (see penta- ), based on the supposed analogy of tera- and tetra- . Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004