The most common and most likely answer to this crossword clue is the 10 letter word ANTISEPTIC
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More clues leading to the result ANTISEPTIC
- Patient is treated with cold disinfectant
- Extremely clean pants etc I repeatedly laundered (100
- Clinical test I panic about
- Endlessly sick patient treated getting clean
- Worker perhaps is heroic, keeping middle of factory clean
- Clean six-footer having one month in charge
- Arrangement of pittance is cold
- Iodine for one upsetpatient
- Bland caper occurring around start of month
Buddy explains!

The straight part
We know that "Extremely clean" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case extremely clean = antiseptic.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 ANTISEPTIC mean?
ANTISEPTIC noun- Any substance that inhibits the growth and reproduction of microorganisms. Generally includes only those that are used on living objects (as opposed to disinfectants) and aren't transported by the lymphatic system to destroy bacteria in the body (as opposed to antibiotics).
- Of, or relating to antisepsis, or the use of antiseptics.
- (pharmaceutical effect) Capable of preventing microbial infection.
- Very clean; aseptic.
- Free of unpleasantness; prim, sanitized or bowdlerized.