Pertaining to or resembling hair: as, a capillary lotion; capillary fibers or threads.Specifically, in botany, resembling hair in the manner of growth: applied in this sense by Ray, Boerhaave, and other early botanists to ferns.Resembling a single hair; specifically, in anatomy, having (as a tube) so small a bore that water cannot be poured into it, and will not run through it.Pertaining to a capillary or to capillaries: as, capillary circulation.Pertaining to the phenomena of the rise of fluids in tubes and chinks, and, more generally, to the collecting of liquids in drops, their spreading over surfaces (as oil on water), and various other phenomena explicable proximately by surface-tension and ultimately by cohesion and adhesion, considered as forces acting at finite but insensible distances.In surgery, linear: descriptive of a fracture of the skull without separation of the parts of the injured bones.n. pl. capillaries (-riz).n. A tube with a small bore. Specificallyn. In anatomy: One of the minute blood-vessels which form a network between the terminations of the arteries and the beginnings of the veins.n. One of the minute lymphatic ducts.n. One of the intercellular passages in the liver which unite to form the bile-ducts.n. In botany, a fern: especially applied to such ferns as grow like tufts of hair on walls. Sir T. Browne. See I., 2.