The most common and most likely answer to this crossword clue is the 5 letter word MINIM
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N
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More clues leading to the result MINIM
Buddy explains!

The straight part
We know that "note" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case note = minim.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 MINIM mean?
MINIM noun- A half note, drawn as a semibreve with a stem.
- A unit of volume, in the Imperial and U.S. customary systems, 1/60 fluid drachm. Approximately equal to 1 drop, 62 μL or 0.9 grain (weight) of water.
- A short vertical stroke used in handwriting.
- Anything very minute; applied to animalcula and the like.
- The smallest kind of worker in a leaf-cutter ant colony.
- A little man or being; a dwarf.
- A small fish; a minnow.
- A short poetical encomium.