Toothed Whale With Long, Protruding, Helical Tusk
Puzzle 7 of Deep Sea Journey Hard Pack
Question is: Toothed Whale With Long, Protruding, Helical Tusk
and the answer is: NARWHAL
Word Meaning:
NARWHAL — An Arctic toothed whale (Monodon monoceros) that grows to about 20 feet (6 meters) long, the male having a single horn-like tusk, a twisted, pointed cuspid that projects forward.
Definitions from Wiktionary.