The most common and most likely answer to this crossword clue is the 9 letter word COLERIDGE
I've seen this crossword clue in The Guardian
C
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More clues leading to the result COLERIDGE
- Romantic pass finally made before watershed?
- Poet going north: ‘Say, frightful water in Scotland, mostly’
- Between mountain pass and narrow elevation, English versifier
- He wrote poems about revolting greed and oil
- Samuel, free to enter university, left out
- Poet made clear in heartless academy
- Poet using energy between pass and hilltop
- Romantic poet and old king on mountain top?
- Leo cried terribly absorbing good poet
- Poet going north: 'Say, frightful water in Scotland, mostly'
Buddy explains!

The straight part
We know that "Samuel" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case samuel = coleridge.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.