Cryptic crossword clue
Theoretical problem’s missing a measurement of volume 10

The most common and most likely answer to this crossword clue is the 10 letter word HECTOLITRE

I've seen this crossword clue in Financial Times
H
E
C
T
O
L
I
T
R
E

Buddy explains!

The straight part
We know that "measurement of volume" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case measurement of volume = hectolitre.
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 HECTOLITRE mean?

HECTOLITRE noun
  1. A unit of volume or capacity equivalent to 100 litres. Symbol: hL

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