Definition of M-16 in US English:

M-16

noun

  • A lightweight, fully automatic assault rifle that shoots small-caliber bullets at an extremely high velocity, used by US troops after 1966.

    • ‘Ashdod police were more than a bit surprised on Sunday when they spotted a 5-year-old walking a local street brandishing an M-16 rifle.’
    • ‘Kidding, it's not really a DeWalt edition rifle, it's just an M-16 some guy modded to look like one.’
    • ‘"I could troubleshoot an M-16 much faster than I could an M-14," says Lieut. Colonel Henry Miller, chief of Army heavy maintenance in Saigon.’