Cryptic crossword clue
Vacant attendant serving powerless old prince 8

The most common and most likely answer to this crossword clue is the 8 letter word ATHELING

I've seen this crossword clue in The Times
A
T
H
E
L
I
N
G

Buddy explains!

The straight part
We know that "old prince" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case old prince = atheling.
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 ATHELING mean?

ATHELING noun
  1. A prince, especially an Anglo-Saxon prince or royal heir.

Latest crossword clues with full explanations