Definition of Allen screw in English:

Allen screw

noun

trademark
  • A screw with a hexagonal socket in the head.

    • ‘The standard pin has a larger head complete with an Allen screw for locking in place.’
    • ‘One of the really nice things about the little rifle is that changing barrels is very easy - simply remove two Allen screws.’
    • ‘There's also an Allen screw tension adjustment to regulate how tightly the pistol is held.’
    • ‘All you have to do is loosen - and then tighten - two Allen screws to change barrels.’
    • ‘Both blued and stainless versions are offered with an Allen screw in the head of the pin that can be tightened against the bottom of the barrel to prevent movement under recoil.’

Origin

1930s: from the name of the manufacturer (see Allen key).

Pronunciation

Allen screw