Regretful when running out of fuel after a right turn (6)
I believe the answer is:
rueful
'regretful' is the definition.
(I've seen this before)
'running out of fuel after a right turn' is the wordplay.
I cannot really see how this works, but
an anagram of 'fuel' is 'eful' which is within the answer.
'right' could be 'r' (common abbreviation) and 'r' is found in the answer.
'turn' could be 'u' (a 'U-turn' is a kind of turn) and 'u' is located in the answer.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
'when' acts as a link.
Can you help me to learn more?
(Other definitions for rueful that I've seen before include "Regretting" , "Apologetic" , "Melancholy" , "Regretful" , "Repentant" .)