The most common and most likely answer to this crossword clue is the 8 letter word ADJUTANT
I've seen this crossword clue in The Times
A
D
J
U
T
A
N
T
More clues leading to the result ADJUTANT
- Officer pulling wings off lady beetle and termite
- Project worker under notice becoming military aide
- Notice worker accepting project for military assistant
- Plug project supported by soldier, say, and officer
- Notice project given to soldier, possibly an officer
- Notice project worker, one assisting senior officer
- Officer and worker giving backing to commercial project
- Notice fibre lacking in English soldier who assists senior officer?
- Military assistant gives notice to project worker
- Officer with a jacket starts to upbraid tetchy worker
Buddy explains!

The straight part
We know that "Officer" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case officer = adjutant.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 ADJUTANT mean?
ADJUTANT noun- A lower-ranking officer who assists a higher-ranking officer with administrative affairs.
- An assistant.
- Any bird of the genus Leptoptilos, a branch of the stork family (Ciconiidae) native to India and Southeast Asia.
- Assistant; who helps a higher-ranking officer.