The most common and most likely answer to this crossword clue is the 8 letter word THINKING
I've seen this crossword clue in The Sunday Telegraph
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More clues leading to the result THINKING
- Rational article about family
- Rational but erroneous description of Henry VIII
- Weak royal judgement
- Contemplative monarch of slender build
- As at first, Henry VIII was intellectual
- Fine head — using it?
- It couldn’t describe Henry VIII’s judgment
- Tenuous piece of logic
- Philosophy of weak leader
- Fine man for philosophy
Buddy explains!
The straight part
We know that "rationale" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case rationale = thinking.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 THINKING mean?
THINKING noun- Thought; gerund of think.
- To ponder, to go over in one's head.
- To communicate to oneself in one's mind, to try to find a solution to a problem.
- To conceive of something or someone (usually followed by of; infrequently, by on).
- To be of opinion (that); to consider, judge, regard, or look upon (something) as.
- To guess; to reckon.
- To plan; to be considering; to be of a mind (to do something).
- To presume; to venture.
- To seem, to appear.