The most common and most likely answer to this crossword clue is the 6 letter word FECUND
I've seen this crossword clue in The Guardian
F
E
C
U
N
D
More clues leading to the result FECUND
- Fruitful supply across the City
- Prolific source of money around City
- Greatly productive association of states fills money reserve
- Iron, copper and no end of silica – very productive
- Point to a hundred in stock that’s prolific
- City investment is about to be productive
- City of London finance assumed to be productive
- Rich capital city bores
- Put money into protecting European Community? That’ll be fruitful!
- Prolific heartless eccentric protected by endowment
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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 FECUND mean?
FECUND adjective- Highly fertile; able to produce offspring.
- Leading to new ideas or innovation.