P / plaustrum
noun

plaustrum

gen. plaustrae · gender feminine · decl. 1st
(, Cato, R. R. 2, 10; 62; Varr. R. R. 1, 22, 3; cf. Suet. Vesp. 22:
a wagon; wain; cart
v. infra), i, n. Sanscr. plavas, ship; prop., that which sways hither and thither; root plu-; Gr. πλέω, πλύνω, a vehicle for carrying heavy loads, a wagon, wain, cart.
Lit. (class.): vendat plostrum vetus, Cato, R. R. 2, 7; Plaut. Aul. 3, 5, 31: in plaustrum conici, Cic. Div. 1, 27, 57: stridentia plaustra, Ov. Tr. 3, 10, 59; id. M. 2, 177: sicut stridet plaustrum onustum foeno, Vulg. Amos, 2, 13: tecta, id. Num. 7, 3.—Prov.: plaustrum perculi, I have upset! I am done for! Plaut. Ep. 4, 2, 22.—
the constellation Charles's Wain; the Great Bear by extension
Transf., the constellation Charles's Wain, the Great Bear (poet.): flexerat obliquo plaustrum temone Bootes, Ov. M. 10, 447; id. P. 4, 10, 39; Amm. 15, 10, 2 (called plaustra Parrhasis, Sid. Carm. 5, 282 sq.).