abluminal

adjective
ab·​lu·​mi·​nal | \ ˌab-ˈlü-mə-nᵊl How to pronounce abluminal (audio) \
variants: also ablumenal

Medical Definition of abluminal

: forming, involving, or occurring on the outer surface of a body part or device with an internal cavity or channel : not adjacent to the lumen of a tubular organ or part … the abluminal surface of the stent …— Ron Waksman, The Lancet, 3 Oct. 2008 We have observed that the individual extravasated cells extend pseudopodial projections that wrap around the abluminal surface of vessel … — Ann F. Chambers et al., in Advances in Cancer Research, 2000