The most common and most likely answer to this crossword clue is the 8 letter word FOREWORD
I've seen this crossword clue in Financial Times
F
O
R
E
W
O
R
D
More clues leading to the result FOREWORD
Buddy explains!
The straight part
We know that "Preface" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case preface = foreword.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 FOREWORD mean?
FOREWORD noun- An introductory section preceding the main text of a book or other document; a preface or introduction.