Lewis Short
prūna (noun F) : root in Gr. πῦρ, fire
* A burning coal, live coal (cf. carbo): medium per ignem multā premimus vestigia prunā,Verg. A. 11, 788 Serv.; 5, 103: latum clavum prunaeque batillum,Hor. S. 1, 5, 36; Plin. 20, 6, 23, § 54; 29, 3, 11, § 45 al.
Charlton T. Lewis, Charles Short, A Latin Dictionary