The most common and most likely answer to this crossword clue is the 8 letter word CETACEAN
I've seen this crossword clue in The Daily Telegraph
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More clues leading to the result CETACEAN
- Marine creature expert gets a name after swimming etc.
- Whale of an ace, etc, played
- Empty, Charlie can eat cooked sea creature
- Greek islander having no right to catch fabulous sea creature
- Marine mammal a sleuth turned up atop sea
- A deep sea diver who doesn’t often come up for air
- Part of school’s religious group attending service in shade
- Whale of a time over in an EEC country, initially touring
- . Unusual act around eastern sea: pushing out old whales, for one
- Whale’s time with expert in the sea, nothing less
Buddy explains!
The straight part
We know that "Marine mammal" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case marine mammal = cetacean.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does CETACEAN mean?
CETACEAN noun- An animal belonging to the order Cetacea, including dolphins, porpoises, and whales.
- Pertaining to the zoologic order Cetacea, or associated with species falling under that taxonomic hierarchy.
- (by extension, sometimes figurative) Resembling or relating to large aquatic mammals.