[TA] intrinsic laryngeal muscle; origin, muscular process of arytenoid cartilage; insertion, summit of arytenoid cartilage of opposite side and continues as the aryepiglottic muscle in the aryepiglottic fold to the epiglottis; action, narrows or closes the interarytenoid portion of the rima glottidis; nerve supply, recurrent laryngeal. SYN: musculus arytenoideus obliquus [TA], arytenoideus.