The most common and most likely answer to this crossword clue is the 5 letter word SORRY
I've seen this crossword clue in The Sunday Telegraph
S
O
R
R
Y
More clues leading to the result SORRY
- It’s my fault wife leaves trouble for soprano
- Apologetic with small truck not starting
- What runs repeatedly in story, oddly so
- Deplorable learner’s abandoned second vehicle
- Repentant, eh?
- Second vehicle’s open-top, pathetic!
- Extremely poor segment of grass or rye
- Small concern: losing the opener is unfortunate
Buddy explains!

The straight part
We know that "Repentant/eh" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case repentant/eh = sorry.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 SORRY mean?
SORRY noun- The act of saying sorry; an apology.
- (of a person) Regretful for an action; grieved or saddened, especially by the loss of something or someone.
- Poor, pitifully sad or regrettable.
- Pathetic and inferior to the point of causing others disgust.
- Expresses regret, remorse, or sorrow.
- Used as a request for someone to repeat something not heard or understood clearly.
- Used to correct oneself in speech.