Many English verbs end in the suffix /aɪz/. Historically, this has been spelled -ize on words coming from Greek (for example baptize, Hellenize), while -ise has been used, especially in -vise, -tise, -cise, and -prise, on words coming from French or Latin (for example surprise, supervise). In the 19th century, it became common in the United Kingdom (due to French influence), and then also in Ireland, India, Australia, and New Zealand, to use -ise on words that had historically been spelled -ize (hence baptise, Hellenise). However, the influential Oxford University Press and its Oxford English Dictionary continued to use the spelling -ize on Greek words, and -ize has always been the spelling used in the United States and the predominant one in Canada on such words.
