Ox-tongue; a genus of the polygamia squamosa order, belonging to the syngenesia class of plants. There are four species, of which the only remarkable one is the echinoides, or common ox-tongue, growing spontaneously in corn-fields in Britain. It has undivided leaves embracing the stem, with yellow blossoms, which sometimes close soon after noon, at other times remain open till nine at night. It is an agreeable pot-herb while young. The juice is milky, but not too acrid.