Steam Locomotive, the World’s Fastest in 1938
Puzzle 19 of Common Dreams Hard Pack
Question is: Steam Locomotive, the World’s Fastest in 1938
and the answer is: MALLARD
Word Meaning:
MALLARD — (countable) Anas platyrhynchos, a common and widespread dabbling duck, natively found throughout the Northern Hemisphere, whose male has a distinctive dark green head.
Definitions from Wiktionary.