The most common and most likely answer to this crossword clue is the 6 letter word TEEMED
I've seen this crossword clue in The Guardian
T
E
E
M
E
D
Buddy explains!

The straight part
We know that "abounded" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case abounded = teemed.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 TEEMED mean?
TEEMED verb- To be stocked to overflowing.
- To be prolific; to abound; to be rife.
- To bring forth young, as an animal; to produce fruit, as a plant; to bear; to be pregnant; to conceive; to multiply.
- To empty.
- To pour (especially with rain)
- To pour, as steel, from a melting pot; to fill, as a mould, with molten metal.
- To think fit.