Penthorum (pen thorum)

[NL. (Linnæus, 1753), so called with ref. to the numerical symmetry; pen tonk i on (pen-tong'ki-on), n.; pl. pentonkia (-a). [ Arsenic pentoxid. See arsenic. pen-tray (pen'trā), n. A small tray or dish, usually long and narrow, used for holding pens penumbra and pen-handles: they are sometimes made highly decorative. A Persian lacquered pen - tray . Catalogue of Duke of Hamilton's Collection, No. 231. pent-roof (pent'röf), n. In arch ., a roof formed like an inclined plane, the slope being all on one side. Also called shed - roof .