IPA: //ˈpɛntaɪˌsaɪd//
KK: /pɛnˈtɒksaɪd/
A chemical compound that consists of five oxygen atoms bonded to another element or group.
Pentoxide is often used in various chemical reactions and processes.
Pentoxide → It is formed from "penta-" (from Greek "pente", meaning five) and "oxide" (from Latin "oxydum", meaning acid or oxygen compound). The word "pentoxide" refers to a chemical compound containing five oxygen atoms.
Think of 'penta-' meaning five, and 'oxide' referring to an oxygen compound — so pentoxide is a compound with five oxygen atoms.