Peta-

Peta (/ˈpɛtə/) is a decimal unit prefix in the metric system denoting multiplication by 1015 (1000000000000000). It was adopted as an SI prefix in the International System of Units in 1975, and has the symbol P. Peta (/ˈpɛtə/) is a decimal unit prefix in the metric system denoting multiplication by 1015 (1000000000000000). It was adopted as an SI prefix in the International System of Units in 1975, and has the symbol P. Peta is derived from the Greek πέντε, meaning 'five'. It denotes the fifth power of 1000 (10005). It is similar to the prefix penta ('five'), but without the letter n (on the analogy of the prefix tera for 10004 looking like tetra- with a letter missing).