The most common and most likely answer to this crossword clue is the 7 letter word COHERED
I've seen this crossword clue in The Times
C
O
H
E
R
E
D
More clues leading to the result COHERED
Buddy explains!

The straight part
We know that "Held good" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case held good = cohered.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 COHERED mean?
COHERED verb- To stick together physically, by adhesion.
- To be consistent as part of a group, or by common purpose.