dum-dum
n.— «When he returned in ’03, McLain was equipped with a thick cushion to wear atop his helmet (he refers to it as a “dum-dum”), which softened any potentially dangerous blows to the head.» —“McLain Making Progress” by Mitch Dobbs ‘Bama (Al.) June 24, 2004. (source: Double-Tongued Dictionary)
Further reading
What if, instead of being an inanimate object, a dictionary were alive? That’s the idea behind a lavishly illustrated new children’s book called The Dictionary Story (Bookshop|Amazon) by Oliver Jeffers and Sam Winston. This is part of a...
David says that when he was growing up in Akron, Ohio, his family referred to the grassy area between the sidewalk and street as the devil strip. He’s since moved to Nashville, Tennessee, where he doesn’t hear that term. There are lots...