PICO- Meaning of PICO- in English [ 'pi:kəʊ , 'pʌɪkəʊ ]■ combining form denoting a factor of 10 -12 : picosecond.↘very small: picornavirus. Originfrom Sp. pico , lit. 'beak, peak, little bit'. Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004