/pe"treuh nl/ , n.
a firearm of large caliber, used from the 15th to the 17th century, that fired with its butt resting against the chest.
[ 1570-80; petrinal, dial. var. of poitrinal, equiv. to poitrine chest ( pectorina, n. use of fem. of * pectorinus of the breast; see PECTORAL, -INE 1 ) + -al -AL 1 ]