Unicorn of the Sea
This page is the CodyCross answer for the clue below from Top Secret, Group 2089, Puzzle 3 (Security Clearance).
Question is: Unicorn of the Sea
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.