👉 Unrefulgent is a term in linguistics that refers to a structure or pattern of sounds that are not harmonically consistent, i.e., which do not produce a full vowel sound. This can be seen as an example of a consonant cluster that does not produce a vowel sound. For instance, the word "un" has two unrefulgent clusters: "un-". The first one is a consonant cluster that sounds like "u", while the second one is a vowel