The most common and most likely answer to this crossword clue is the 13 letter word MONEY-SPINNER
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More clues leading to the result MONEY-SPINNER
Buddy explains!
The straight part
We know that "It brings gain" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case it brings gain = money-spinner.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 MONEY-SPINNER mean?
MONEY-SPINNER noun- Something that generates a continuous income.
- A money spider.