The most common and most likely answer to this crossword clue is the 6 letter word KELVIN
K
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L
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Buddy explains!
The straight part
We know that "Temperature scale/Temperature scale" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case temperature scale/temperature scale = kelvin.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 KELVIN mean?
KELVIN noun- In the International System of Units, the base unit of thermodynamic temperature; 1/273.16 of the thermodynamic temperature of the triple point of water. Shown as "K".
- A unit interval on the Kelvin scale.
- (usually as postpositioned adjective) A unit for a specific temperature on the Kelvin scale.