The most common and most likely answer to this crossword clue is the 10 letter word SCIENTIFIC
I've seen this crossword clue in The Times
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More clues leading to the result SCIENTIFIC
- Analytical exercise incites bathroom cleaner to be recalled
- Insect flutters if one gets caught how biologist’s described?
- Fancy cities mostly find Conservative to be methodical
- Orderly dispatched round Channel Islands, provided freeze decreased
- Methodical setter cracks trail provided by Spinner's opening to crossword
- Methodical hospital department I found in Asimov’s books about . . . ..
- Customer's out of line, though outwardly so rational
Buddy explains!
The straight part
We know that "rational" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case rational = scientific.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 SCIENTIFIC mean?
SCIENTIFIC adjective- Of, or having to do with science.
- Having the quality of being derived from, or consistent with, the scientific method.
- In accord with procedures, methods, conduct and accepted conventions of modern science.