mastic/ˈmæstɪk; `mæstɪk/ n[U]1 gum or resin from the bark of certain trees, used in making varnish 乳香树脂.2 type of pliable cement used for waterproofing joints in window-frames, roofs, etc 胶合铺料, 胶粘水泥（作窗框、 屋顶等填缝防水用的）.
牛津英汉双解词典