The most common and most likely answer to this crossword clue is the 4 letter word IONS
I've seen this crossword clue in The Guardian
I
O
N
S
More clues leading to the result IONS
- They are charged and kept in station sometimes
- They are naturally charged for half portions
- Very small particles found in a television set
- Particles found in 40% of surgical procedures
- They are charged in public houses for a little naughty love
- Particles make noise endlessly
- Setter and son confused about charged particles
- Things never free of charge in clubs that exclude Republicans
- Primarily infinitesimal objects; negative, sometimes?
Buddy explains!
The straight part
We know that "Very small particles" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case very small particles = ions.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 IONS mean?
IONS noun- An atom or group of atoms bearing an electrical charge, such as the sodium and chlorine atoms in a salt solution.