vascular circle

vas·cu·lar cir·cle

1. circumferential formation of arteries and/or veins. 2. the circle around the mouth formed by the inferior and superior labial arteries; 3. Synonym(s): areolar venous plexus Synonym(s): circulus vasculosus [TA]

vascular circle

(1) Areolar venous plexus; plexus venosus areolaris [NA]. 
(2) The anastomosing vascular network formed by the inferior and superior labial arteries.