Swell position for avoiding run-outs? (8)
I believe the answer is:
increase
'swell' is the definition.
(thesaurus)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for increase that I've seen before include "boost" , "Make or grow larger" , "'Augment, expand (8)'" , "Add, make bigger" , "Augment or enlarge (8)." .)