Faint pretty quickly out West (5)
I believe the answer is:
swoon
'faint pretty' is the definition.
'swoon' can be an answer for 'faint' (synonyms). I'm not certain of the 'pretty' bit.
'quickly out west' is the wordplay.
'quickly' becomes 'soon' (I've seen this in other clues).
'out' means one lot of letters goes inside another.
'west' becomes 'W' (abbreviation).
'soon' going around 'w' is 'SWOON'.
Can you help me to learn more?
(Other definitions for swoon that I've seen before include "Fall fainting" , "Display of extreme emotion" , "experience ecstasy" , "Pass out" , "Lose consciousness" .)