The most common and most likely answer to this crossword clue is the 9 letter word ITALICISE
I've seen this crossword clue in Financial Times
I
T
A
L
I
C
I
S
E
More clues leading to the result ITALICISE
- Put slant on appeal: one’s encapsulated by Lewis’s girl
- Type inclined to show stress
- Appeal is penned by girl to make text stand out
- Put on a slope, it is held by girl
- Use distinctive type to stress facilities left by France
- Make stuff like spaghetti?
- Underline it — Alice is inside
- In email, make a big deal of fervent felicitations without wacky font
Buddy explains!

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.
Crossword Answer definitions
ITALICISE verb- To put into italics.
- To emphasize.