The most common and most likely answer to this crossword clue is the 7 letter word EXPLAIN
I've seen this crossword clue in The Times
E
X
P
L
A
I
N
More clues leading to the result EXPLAIN
- Give a justification for former patent
- Describe partner that was unattractive
- Gloss ruined axle pin
- Old and unexciting - tell me why?
- Describe former flat
- Solve old jumbo you’ve picked up?
- Account for one dumped on prairie
- Account for old grassland
- Account for former partner getting even
- Account for former partner, one in scheme
Buddy explains!

The straight part
We know that "Solve" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case solve = explain.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 EXPLAIN mean?
EXPLAIN verb- To make plain, manifest, or intelligible; to clear of obscurity; to illustrate the meaning of.
- To give a valid excuse for past behavior.
- To make flat, smooth out.
- To unfold or make visible.
- To make something plain or intelligible.