仲介物

(1)a bodily passage or tube lined with epithelial cells and conveying a secretion or other substance; "the tear duct was obstructed"; "the alimentary canal"; "poison is released through a channel in the snake's fangs"

(2)上皮細胞で内側を覆われ、分泌または他の物質を運んでいる身体の通路または管

(3)a passage for water (or other fluids) to flow through; "the fields were crossed with irrigation channels"; "gutters carried off the rainwater into a series of channels under the street"

(4)水（または他の流体）が流れる通路

(1)