The most common and most likely answer to this crossword clue is the 8 letter word ACTUALLY
I've seen this crossword clue in The Sunday Telegraph
A
C
T
U
A
L
L
Y
More clues leading to the result ACTUALLY
- Work with university pal, in fact
- Really unfortunate start in current score
- To tell the truth in a court, you reported friend
- Turn on United supporter as it happens
- Really perform with partner, about undressed initially
- Even American clubs score to catch United
- Performance needs superior accomplice, in fact
- A Conservative supporter accepts workers’ organisation, in fact
- Work with university colleague, in fact
- If truth be told, account total hides a bit of unscrupulousness
Buddy explains!

The straight part
We know that "in fact" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case in fact = actually.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 ACTUALLY mean?
ACTUALLY adverb- (modal) In act or in fact; really; in truth; positively.
- Actively.