The most common and most likely answer to this crossword clue is the 7 letter word CAVE-IN
I've seen this crossword clue in The Times
C
A
V
E
-
I
N
Buddy explains!
The straight part
We know that "Surrender" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case surrender = cave-in.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 CAVE-IN mean?
CAVE-IN noun- The act of something collapsing or caving in.
- The location where something has caved in.
- The act of relenting.