The most common and most likely answer to this crossword clue is the 4 plus 5 letter word RAIN GAUGE
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More clues leading to the result RAIN GAUGE
- One can tell how much wet weather we've had
- Anger about home, awkward, not half - it lets in water
- Arguing violently about a drug, drops measuring equipment
- Drops measuring device?
- Liquid in garage boxes for all to see, one can measure water
- Period overseeing fruit mentioned in outdoor assessment?
- Drops measuring equipment
- Measuring device for cats and dogs
- Vehemently arguing about a principal error in instrument measuring drops
- Instrument used to measure cats and dogs?
Buddy explains!

The straight part
We know that "instrument measuring drops" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case instrument measuring drops = rain gauge.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.