Entry 1 sense Webster, 1913 Azygous · Az·y·gous · IPA /eɪˈzaɪɡəs/ 01 a. Odd; having no fellow; not one of a pair; single; as, the azygous muscle of the uvula. 1. Odd; having no fellow; not one of a pair; single; as, the azygous muscle of the uvula.