The most common and most likely answer to this crossword clue is the 5 letter word LORIS
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More clues leading to the result LORIS
- Forest primate getting energy from small parrots
- Primate is following God for the most part
- One’s preceded by gracious primate proceeding slowly
- Primate originally lived on rocky island
- Monkey found in Israel or Islamabad
- Primate's teaching is used for English
- Primate’s brother’s inviting one in
- Primate is seen with nobleman, mostly
- See, teacher upset tree-dweller
- Primate stripped off plant seller
Buddy explains!

The straight part
We know that "Nocturnal primate" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case nocturnal primate = loris.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 LORIS mean?
LORIS noun- Any of several small, slow-moving primates, of the family Lorisidae, found in India and southeast Asia.