The most common and most likely answer to this crossword clue is the 7 plus 6 letter word CARRIER PIGEON
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More clues leading to the result CARRIER PIGEON
- Woman runs business, one conveying messages by air
- Bird's rotting flesh cut by beast feeding before
- Messenger taking the aerial route?
- Flier from prior age, nicer somehow
- Creature with message in horror film, quietly breaking equipment over time
- Winged messenger
- Horror story and awful gripe about messenger
- Smart bird, very good, kept inside cage in error, unfortunately
- What brings word of source of avian flu?
- A bishop in epic region recreated Homer
Buddy explains!

The straight part
We know that "messenger" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case messenger = carrier pigeon.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 CARRIER PIGEON mean?
CARRIER PIGEON noun- A domestic pigeon which transports attached messages or very small parcels from the place where it is released to a familiar destination.