The most common and most likely answer to this crossword clue is the 7 letter word DISPORT
I've seen this crossword clue in The Times
D
I
S
P
O
R
T
Buddy explains!

The straight part
We know that "Play about" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case play about = disport.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 DISPORT mean?
DISPORT noun- Anything which diverts one from serious matters; a game, a pastime, a sport.
- Amusement, entertainment, recreation, relaxation.
- The way one carries oneself; bearing, carriage, deportment.
- Bearing, elevation, orientation.
- Fun, gaiety, joy, merriment, mirth.
- To amuse oneself divertingly or playfully; in particular, to cavort or gambol.