OI and OY Sound Words

Diphthong OY/OI at a glance:

• Words with oi sound include oil, coin, voice
• Words with oy sound include boy, royal, enjoy

Spelling Frequencies:

• oi - 66%
• oy - 34%

Rare Spelling Patterns:

• uoy (buoy)

Common Spelling Generalisations or Patterns:

• English words do not end in ‘i’
• oi typically occurs in the middle and sometimes at the beginning of a word e.g. oil, oink, boil, coin
• oy typically occurs at the end of a syllable or word e.g. toy, boy, employ, joyful, oyster