The most common and most likely answer to this crossword clue is the 7 letter word CELSIUS
I've seen this crossword clue in The Daily Telegraph
C
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L
S
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More clues leading to the result CELSIUS
Buddy explains!
The straight part
We know that "Scale" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case scale = celsius.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 CELSIUS mean?
CELSIUS adjective- Related to a metric temperature scale, originally defined as having the freezing point of water as 0 degrees and its boiling point as 100 degrees, at standard atmospheric pressure. The standardized definition has 0.01 °C as the triple point of water, and a difference in temperature of 1 °C corresponds to 1/273.16 of the difference in temperature between the triple point and the absolute zero.