The most common and most likely answer to this crossword clue is the 7 letter word HABITUE
I've seen this crossword clue in The Times
H
A
B
I
T
U
E
More clues leading to the result HABITUE
- Regular shade used outside a little
- Frequent visitor rather enthralled by southeast Asian city
- Regular visitor put somewhat in shade
- Regular tone, slightly cutting?
- One attending regularly – not a lot – put in appearance
- He often resorts to a piece in colour
- Regular dress for sister, not even used
- Regular customer‘s slightly boring tone
- Regular attendant sees a drop in colour
- Regular visitor somewhat put in shade
Buddy explains!

The straight part
We know that "Frequent visitor" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case frequent visitor = habitue.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 HABITUE mean?
HABITUE noun- One who frequents a place.
- A devotee.