The most common and most likely answer to this crossword clue is the 10 letter word APPEARANCE
I've seen this crossword clue in The Times
A
P
P
E
A
R
A
N
C
E
More clues leading to the result APPEARANCE
- Show a little vegetable in spring
- Advent plant swallowed by a reindeer almost
- Advent roast in a church with fruit stuffing
- Look — seed inside a caper
- One turns up to put one in
- Bearing introduction
- One’s put in by an attendant
- One may turn up to put one in
- A quiet dance introduces each show
- An ace paper struggling to make a showing
Buddy explains!

The straight part
We know that "Show" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case show = appearance.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 APPEARANCE mean?
APPEARANCE noun- The act of appearing or coming into sight; the act of becoming visible to the eye.
- A thing seen; a phenomenon; an apparition.
- The way something looks; personal presence
- Apparent likeness; the way which something or someone appears to others.
- That which is not substance, essence, hypostasis; the outward reality as opposed to the underlying reality
- The act of appearing in a particular place, or in society, a company, or any proceedings; a coming before the public in a particular character.
- An instance of someone coming into a court of law to be part of a trial, either in person or represented by an attorney or such like; a court appearance
- Chiefly used by nurses: the act of defecation by a patient.