The most common and most likely answer to this crossword clue is the 8 letter word NEUTRINO
I've seen this crossword clue in The Guardian
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More clues leading to the result NEUTRINO
- Report of addition to forest: be aware it’s difficult to detect
- Tour 9 runs, one moving with the speed of light?
- Urine not flowing? It’s definitely not a big thing!
- New woody plant discussed? No, science gives it little weight
- Turn-on that is arranged for one without any charge
- Arranged tour in north-east — it’s free of charge
- It’s minute ’n’ massless
- One Turin game that’s free of charge
- Rumour of recent threesome — name’s taken but one’s not charged
- Particle from sapling, perhaps, Ken picked up
Buddy explains!
The straight part
We know that "It’s definitely not a big thing" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case it’s definitely not a big thing = neutrino.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 NEUTRINO mean?
NEUTRINO noun- An elementary particle that is classified as a lepton, and has an extremely small but nonzero mass and no electric charge. It interacts with the surroundings only via the weak force or gravitation, making it very difficult to detect.