Gun

geweer

(less portable, long weapon)

kanon

(military: cannon with relatively long barrel, operating with relatively low angle of fire, and having a high muzzle velocity)

kanon

(military: cannon with tube length 30 calibers or more)

pistool

(portable, short weapon, for hand use)

vuurwapen

(portable, short weapon, for hand use)

vuurwapen

(less portable, long weapon)

opdrijven

(speed something up)