The most common and most likely answer to this crossword clue is the 4 letter word LOAF
I've seen this crossword clue in The Times
L
O
A
F
Buddy explains!

The straight part
We know that "stand around idly" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case stand around idly = loaf.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 LOAF mean?
LOAF noun- (also loaf of bread) A block of bread after baking.
- Any solid block of food, such as meat or sugar.
- Shortened from "loaf of bread", the brain or the head (mainly in the phrase use one's loaf).
- A solid block of soap, from which standard bars are cut.
- To do nothing, to be idle.
- (Cockney rhyming slang) To headbutt, (from loaf of bread)