The most common and most likely answer to this crossword clue is the 11 letter word THERMOMETER
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More clues leading to the result THERMOMETER
- The right doctor assembled emergency room gauge
- The writer put in revised other term for measuring device
- Hot in spell, yet more shivery – not unknown indicator of fever?
- See me hotter, me out of sorts? Right — get this!
- Time that woman’s doctor encountered ruler as measuring device
- Its mercurial rise may indicate need for care
- Measuring instrument — article Republican doctor encountered in front of emergency room
Buddy explains!

The straight part
We know that "Measuring instrument" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case measuring instrument = thermometer.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 THERMOMETER mean?
THERMOMETER noun- An apparatus used to measure temperature.