English Etymology From mid- + axillary. Adjective midaxillary (not comparable) (anatomy) Describing a vertical line on the body downwards from the armpit 2015 July 14, “Mutation in BMPR2 Promoter: A ‘Second Hit’ for Manifestation of Pulmonary Arterial Hypertension?”, in PLOS ONE, →DOI:The zero reference point for pressure recordings was set at the level of the right atrium in the midaxillary line (phlebostatic axis). Remove adsWikiwand - on Seamless Wikipedia browsing. On steroids.Remove ads