es in spelling

A number of words end in -our in British English and -or in American English. Some words end in -er in American English and -re in British English. Many verbs which end in -ize in American English can be spelt in British English with -ize or -ise. In British English -I is doubled in an unstressed syllable before a suffix beginning with a vowel, while in American English it is not doubled.

Some of the commonest words with different spellings are given below.