Defective script

A defective script is a writing system that does not represent all the phonemic distinctions of a language.^{: 36–38 : 118} This means that the concept is always relative to a given language. Taking the Latin alphabet used in Italian orthography as an example, the Italian language has seven vowels, but the alphabet has only five vowel letters to represent them; in general, the difference between the phonemes close /e, o/ and open /ɛ, ɔ/ is simply ignored, though stress marks, if used, may distinguish them. Among the Italian consonants, both /s/ and /z/ are written ⟨s⟩, and both /t͡s/ and /d͡z/ are written ⟨z⟩; stress and hiatus are also not reliably distinguished.