He collated rest and relaxation with ease? (5)
I believe the answer is:
roget
'he collated rest and relaxation with ease?' is the definition.
The definition suggests a singular noun which matches the answer.
'he collated rest' is the wordplay.
'he' becomes 'Rog'.
'collated rest' becomes 'et' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'rog'+'et'='ROGET'
Can you help me to learn more?
(Other definitions for roget that I've seen before include "Scholar remembered for his Thesaurus" , "compiler of reference work" , "Thesaurus inventor" , "Item of clothing; confer" , "The man for the synonyms" .)