The most common and most likely answer to this crossword clue is the 9 letter word FISHERMAN
I've seen this crossword clue in The Guardian
F
I
S
H
E
R
M
A
N
More clues leading to the result FISHERMAN
- Female — is the lady's beau James or John?
- Poem recalled US Civil War commander, one standing on bank?
- Female is on Channel Island with an angler
- Person catching extremists in Ferrari with tank
- Raise provided with general net-worker?
- One might catch Pike or Jack, if backed by tank
- Main worker providing revolutionary war machine
- Angler‘s koi finally put in fine tank?
- James or John? It’s doubtful which tank’s propelled skyward
- US Civil War general’s captivated by exciting piece of papal regalia
Buddy explains!

The straight part
We know that "Main worker/Main worker" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case main worker/main worker = fisherman.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 FISHERMAN mean?
FISHERMAN noun- A fisher, a person engaged in fishing:
- A vessel (boat or ship) used for fishing.