Letter: Spelling corrections

Sir: Peter Fooks, who complained about the use of the word "extravert" in an Independent crossword (Letter from the Editor, 24 January), should check his dictionary. Both spellings are given. Indeed, it might well be the preferred spelling amongst British psychologists.

The Oxford English Dictionary gives both spellings a long history, but for the psychological sense, "extravert" first appeared in 1915, and "extrovert" in 1918 in an American journal, so the latter spelling may well be an Americanism.

PAUL DORMER

Guildford

Surrey