custos

noun

1. (obsolete)A warden.

   “[…] they were commytted to prison & put out of theyr offyces & the Constable of the Towre made custos of the citye.”

   “Mr. Tharp, the Custos of the parish, and several other gentlement, accompanied the corps.”

2. A monastic superior, who, under the general of his order, has the direction of all the religious houses of the same fraternity in a given district, called a custody of the order.
3. (historical)In older forms of musical notation, an indication, at the end of a line of music, of the first note of the next line.