A wet part transformed into readily available liquid (3,5)
I believe the answer is:
tap water
'readily available liquid' is the definition.
'tap water' can be an answer for 'liquid' (tap water is a kind of liquid). I am not sure about the 'readily available' bit.
'a wet part transformed' is the wordplay.
'transformed' is an anagram indicator.
'a'+'wet'+'part'='awetpart'
'awetpart' with letters rearranged gives 'TAP-WATER'.
'into' acts as a link.
Can you help me to learn more?
(Other definitions for tap water that I've seen before include "Ordinary drink" , "Vital liquid from a sink unit" , "cheap drink" , "Domestic drink" , "still running?" .)