Line delivery lands on? (9)
I believe the answer is:
direction
'line' is the definition.
(direction is a kind of line)
'delivery lands on?' is the wordplay.
I cannot really see how this works, but
'on?' could be 're' ('on' can be mean 'with reference to') and 're' is located in the answer.
'delivery' could be 'diction' (I've seen this in other clues) and 'diction' is found within the remaining letters.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for direction that I've seen before include "Management" , "Guidance" , "The way in which something is moving" , "Course along which something moves" , "Course in which something is travelling" .)