The most common and most likely answer to this crossword clue is the 7 letter word COLOGNE
I've seen this crossword clue in The Guardian
C
O
L
O
G
N
E
More clues leading to the result COLOGNE
- Officer gone mad in German city
- Pass over good points in industrial city
- Traffic controller about to enter continental city
- Marker pens record European city
- Somewhere in Germany, solid wood splits
- What 18 never wore when singing aloud, in essence?
- City foremost in commerce one holding record
- Officer’s gone mad for alcoholic mixture
- Pass over German wearing a perfume
- Army officer’s gone wandering in Germany
Buddy explains!

The straight part
We know that "alcoholic mixture" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case alcoholic mixture = cologne.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 COLOGNE mean?
COLOGNE noun- A type of perfume consisting of 2-5% essential oils, 70-90 % alcohol and water.