Vowels 2 and 15, /ɪ/ and /ɔɪ/  62 pairs   [billboil.html]

Vowel /ɪ/ is spelled <i> or <y>. The /ɔɪ/ diphthong is spelled <oi> or <oy>.

I am not aware of any group of learners who have trouble with this distinction.

Interesting pairs include:

hidden hoyden
missed moist

The mean density is 0.3%. The list makes only 26 semantic distinctions, giving a low semantic loading of 42%.

Ali alloy
alley alloy
  alleys alloys
bid buoyed
bill boil
  billed boiled
  billing boiling
  bills boils
biz boys
brill broil
envy envoi 
  envies envois
envy envoy
  envies envoys
fill foil
  filled foiled
  filling foiling
  fills foils
fist foist
  fists foists
gin join
  ginned joined
  ginning joining
  gins joins
gist joist
  gists joists
grin groin
  grinned groined
  grinning groining
  grins groins
hidden hoyden
hissed hoist
ill oil
  ills oils
kill coil 
  killed coiled 
  killing coiling 
  kills coils 
kin coign 
lids Lloyd's 
litter loiter
  littered loitered
  littering loitering
  litters loiters
mill moil
  milled moiled
  milling moiling
  mills moils
missed moist
mist moist
sill soil
  sills soils
spill spoil
  spilled spoiled
  spilling spoiling
  spills spoils
  spilt spoilt
till toil
  tiller toiler
  tillers toilers
  tilling toiling
  tills toils

John Higgins, Shaftesbury, Januaru 2011
updated Chiang Mai, 2024