the "sound-it-out" metric
Some languages are very phonetic; the same small number of rules will let you sound out every word.
English is far less phonetic; there are many words that are pronounced oddly ⚙️ ( the tough ploughman let out a sigh)
Fortunately, we can calculate how "phonetic" a word is. Bat and hat will be very phonetic, colonel and knight and yacht will not be.
💡 this is useful for scoring texts for grade-level.