Memorise renal layout (5)
I believe the answer is:
learn
'memorise' is the definition.
(synonyms)
'renal layout' is the wordplay.
'layout' indicates an anagram (an alternative layout of the letters).
'renal' is an anagram of 'LEARN'.
(Other definitions for learn that I've seen before include "Comprehend" , "Gain knowledge or skill" , "Study or digest" , "Commit to memory" , "Succeed in school" .)