The most common and most likely answer to this crossword clue is the 8 letter word DOLPHINS
I've seen this crossword clue in The Daily Telegraph
D
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P
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More clues leading to the result DOLPHINS
Buddy explains!
The straight part
We know that "they’re supposedly intelligent" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case they’re supposedly intelligent = dolphins.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 DOLPHINS mean?
DOLPHINS noun- A carnivorous aquatic mammal in one of several families of order Cetacea, famed for its intelligence and occasional willingness to approach humans.
- A fish, the mahi-mahi or dorado, Coryphaena hippurus, with a dorsal fin that runs the length of the body, also known for iridescent coloration.
- A depiction of a fish, with a broad indented fin, usually embowed.
- The dauphin, eldest son of the kings of France.
- (history) A mass of iron or lead hung from the yardarm, in readiness to be dropped through the deck and the hull of an enemy's vessel to sink it.
- A kind of wreath or strap of plaited cordage.
- A spar or buoy held by an anchor and furnished with a ring to which ships may fasten their cables.
- A mooring post on a wharf or beach.
- A permanent fender around a heavy boat just below the gunwale.
- One of the handles above the trunnions by which a gun was lifted.
- A man-made semi submerged maritime structure, usually installed to provide a fixed structure for temporary mooring, to prevent ships from drifting to shallow water or to serve as base for navigational aids.