The most common and most likely answer to this crossword clue is the 4 plus 3 plus 5 letter word OVER THE YEARS
I've seen this crossword clue in The Daily Telegraph
O
V
E
R
T
H
E
Y
E
A
R
S
Buddy explains!
The straight part
We know that "through time" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case through time = over the years.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.