This study aims at examining the thoughts of Avecinna concerning phonetics, phonology and semantics, in light of modern linguistics. The study observed that he described the nature of sound, pitch and intensity, and he described the articulation apparatus, especially larynx, thyroid, arytenoids and the cricoid. Then he described evidently the Arabic consonants, firstly the stops, fricatives, laterals, rolleds, and lately the nasals. After that he described the vowels. He added to all of this his view about the relation between the sound and the meaning which looks like the view of contemporary semanticists.