from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A foolish or empty-headed person: "He presents antiwar protesters . . . as bubbleheads who didn't even know where Southeast Asia was” ( Frank Rich).
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A stupid person.
- n. A submariner; bubble-head.
- n. A navy hardhat or salvage diver, inspired by the shape of the old, spun copper diving helmet.
bubble + -head (Wiktionary)