What is "hackbuss"

Hagbut \Hag"but\ (-b[u^]t), n. [OF. haquebute, prob. a corruption of D. haakbus; haak hook + bus gun barrel. See Hook, and 2d Box, and cf. Arquebus.] A harquebus, of which the but was bent down or hooked for convenience in taking aim. [Written also haguebut and hackbuss.]

n. (alternative form of hagbut English)