The most common and most likely answer to this crossword clue is the 6 letter word BARREN
B
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More clues leading to the result BARREN
- Desolate pub gets torn apart, almost
- Unproductive nobleman, by the sound of it
- Unproductive noble, by the sound of it
- Unproductive 8, by the sound of it?
- Engineers accommodated in farm building, dull
- Heard member of upper house is unproductive
- Pub with short lease, empty
- Said noble is without hope of heir
- Unproductive member of the nobility, we hear
- Unproductive noble, according to reports
Buddy explains!

The straight part
We know that "Vapid" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case vapid = barren.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 BARREN mean?
BARREN noun- An area of low fertility and habitation, a desolate place.
- Unable to bear children; sterile.
- Of poor fertility, infertile; not producing vegetation.
- Bleak.
- Unproductive; fruitless; unprofitable; empty.
- Mentally dull; stupid.