bubblehead
n.— «Any old “Bubbleheads” (fer all you land-lubbers that’s slang fer Submariners) who were stationed at New London/Groton during the late 40’s, 50′ and 60’s, I’m sure y’all most certainly remember this landmark.» —“The Bouyant Ascent…Submarine Escape Training Tower” by Cookie The Cook Shack—Gab & Grub (New York) May 12, 2006. (source: Double-Tongued Dictionary)