ceterach; a genus of the order of filices, belonging to the cryptogamia class of plants; of which there are seven species, but only two are natives of Britain. They grow upon old walls or moist rocks; one is called feslopendrium, or hart's tongue; the other is properly ceterach, also called spleenwort. It has an herbaceous, somewhat mucilaginous, roughish taste: it is recommended as a pectoral, and for promoting urine in nephritic cases. The virtue which it has been most celebrated for is that which it has the least title to, viz. diminishing the spleen.