This study investigates the impact of vocalic phonemes—specifically short vowels (fatḥah, ḍammah, and kasrah)—on semantic variation within the Arabic lexicon, with Qutrub’s Triangle as a phonosemantic model. Combining descriptive-analytic and phonological approaches, the research explores how vowel alternation generates different meanings despite the stability of the consonantal root. The study concludes that vowels in Arabic function as meaningful phonemic units capable of semantic distinction, and that early Arab linguists were aware of this phenomenon, as reflected in Qutrub’s model, which anticipates modern phonosemantic theory.