CHAPTER 23

Using oy and oi

While the long vowel sounds produced by oy and oi are exactly the same, there is a logical reason to use

one rather than the other. There are very few exceptions.

Spelling rule #1: The oy is used at the end of a word:

Spelling rule #2: The oi is used in the middle of a word:

(^) Note that the oi must be followed by at least one consonant:
(^) Note that oid is also a suffix meaning “resembling” or “like”:
(^) Very few words start with either oy or oi:
(^) Note that many centuries ago, oyster was spelled oistre.
When adding suffixes, as the y is preceded by a vowel the y is not usually changed to an i.
(^) Three words that retain the y in order to avoid the oia combination are royal, loyal, and voyage. The
oia combination is very rare in English: sequoia and paranoia.