aExtravascular(Anat) Outside the vessels; -- said of the substance of all the tissues.
Century Dictionary and Cyclopedia
extravascularBeing out of the proper vessel or vessels; without distinct vessels: applied especially to the free circulation of the blood of insects between the viscera and the muscles, without special veins or arteries.
extravascularNonvascular: applied to parts which have no blood-vessels: as, cuticle and cartilage are extravascular structures.
Chambers's Twentieth Century Dictionary
Extravascularsituated outside of the vascular system