The most common and most likely answer to this crossword clue is the 5 letter word CHINK
I've seen this crossword clue in The Guardian
C
H
I
N
K
More clues leading to the result CHINK
Buddy explains!
The straight part
We know that "breach/breach" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case breach/breach = chink.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 CHINK mean?
CHINK noun- A narrow opening such as a fissure or crack.
- A chip or dent in something metallic.
- A vulnerability or flaw in a protection system or in any otherwise formidable system.
- To fill an opening such as the space between logs in a log house with chinking; to caulk.
- To crack; to open.
- To cause to open in cracks or fissures.
- A slight sound as of metal objects touching each other; a clink.
- Ready money, especially in the form of coins.
- To make a slight sound like that of metal objects touching.
- To cause to make a sharp metallic sound, as coins, small pieces of metal, etc., by bringing them into collision with each other.
- A convulsive fit of coughing or laughter; a sonorous indraft of breath; a whoop; a gasp of breath caused by laughing, coughing, or crying.
- To laugh loudly.
- To gasp for breath as in a severe fit of coughing.
- A person of perceived Chinese ethnicity.