What does the cryptic crossword clue "Use ace disguise, we hear (5)" mean?

The definition is "Use". The wordplay uses a homophone (sounds like). A (ace), then VAIL sounds like [we hear] “veil” (disguise) The answer is AVAIL.

Use ace disguise, we hear (5)

Times Cryptic #28568 | 14 Across | 2023-04-04 flower