The most common and most likely answer to this crossword clue is the 4 letter word REAP
I've seen this crossword clue in The Guardian
R
E
A
P
More clues leading to the result REAP
Buddy explains!
The straight part
We know that "Collect" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case collect = reap.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 REAP mean?
REAP noun- A bundle of grain; a handful of grain laid down by the reaper as it is cut.
- To cut (for example a grain) with a sickle, scythe, or reaping machine
- To gather (e.g. a harvest) by cutting.
- To obtain or receive as a reward, in a good or a bad sense.
- To terminate a child process that has previously exited, thereby removing it from the process table.
- To deprive of the beard; to shave.