A minute opening in tissue, as in the skin of an animal, serving as an outlet for perspiration, or in a plant leaf or stem, serving as a means of absorption and transpiration.

• 毛孔组织中的微小开口，如动物皮肤中，主要作为出汗孔，或如植物叶子或根茎中者，主要作为吸收及蒸腾作用的途径