This research focuses on a phonetic aspect that falls into three areas, phonetics, dialectology and Arabic sociophonetics. Our approach, tools and analysis are phonetic in nature. We analyzed the frequency of the first three formants [F1, F2, F3] of short cardinal vowels / i, u, a /of the Libyan Arabic of Tripoli (ALT) and we alternated the phonetic context of pharyngealized consonants / t ˁ, s ˁ , ˁ d / versus non pharyngealized / t, s, d / to verify the impact of the latter on the central frequency of formants. However, the results obtained have allowed us to compare the ALT to other popular varieties in modern Arabic. As they allowed us to make fundamental social distinctions, such as the gender. Our research problem deals with the issue of the realization of the acoustic space of vowels in ALT, in contrast with the consonant pharyngealization, the resulting co-articulatory patterns as well as the tool of 'locus equation' to reveal, all of this in a dimension of social stratification by gender. Three hypotheses were presented; the first was on the variation of the vowel space and its motivations, the second was on the appropriateness of using the locus equation and the third was related to gender distinctions. Our results, based on the analysis of a corpus of trisyllabic words [C1V1 C2V2-C3V3-] where C is either a pharyngalized consonant / s ˁ, ˁ t, d ˁ / or a non- pharyngalized consonant / s, t, d /, V is one of the three cardinal short vowels / i, u, a /, read by ten speakers (6 males and 5 females) to validate our three hypotheses. Changes in formant values of vowels, the acoustic space and the distance between the first two formants were based on three factors: 1) the consonantal context (pharyngalized vs. non- pharyngalized), 2) the prosodic position (stressed vs. unstressed), and 3) social distinction (male vs. female). Our study has been able to respond positively to the objectives assigned to it at the start: 1) on the phonetic level, it gives an overview of the vowel system of ALT and its variation with the pharyngealization 2) on the dialectological level, it answers questions from Arabic dialect typology and classification of the Eastern Libyan Arabic dialect vs Maghreb dialect and 3) on the sociophonetic level, it verifies the profound social distinction, woman's speech vs man's speech
