The most common and most likely answer to this crossword clue is the 5 letter word SHERD
I've seen this crossword clue in Financial Times
S
H
E
R
D
More clues leading to the result SHERD
Buddy explains!

The straight part
We know that "Broken piece" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case broken piece = sherd.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 SHERD mean?
SHERD noun- A piece of broken glass or pottery, especially one found in an archaeological dig.
- (by extension) A piece of material, especially rock and similar materials, reminding of a broken piece of glass or pottery.
- A tough scale, sheath, or shell; especially an elytron of a beetle.
- An instance of an MMORPG that is one of several independent and structurally identical virtual worlds, none of which has so many players as to exhaust a system's resources.
- A component of a sharded distributed database.
- (singular or plural) A piece of crystal methamphetamine.