The most common and most likely answer to this crossword clue is the 7 letter word DEITIES
I've seen this crossword clue in The Daily Telegraph
D
E
I
T
I
E
S
More clues leading to the result DEITIES
Buddy explains!

The straight part
We know that "Olympians" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case olympians = deities.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 DEITIES mean?
DEITIES noun- A supernatural divine being; a god or goddess.
- The state, position, or fact of being a god or God. [from 14th c.]
- A celestial being inferior to a supreme God but superior to man.
- The study of religion or religions.
- A type of confectionery made with egg whites, corn syrup, and white sugar.