Section of choir temporarily recalled group (4)
I believe the answer is:
trio
'group' is the definition.
(a group of three)
'section of choir temporarily recalled' is the wordplay.
'section of' indicates a hidden word.
'recalled' is a reversal indicator.
'oirt' can be found hidden inside 'choir temporarily'.
'oirt' written backwards gives 'TRIO'.
(Other definitions for trio that I've seen before include "Chamber group" , "Beethoven's 'Archduke', for instance" , "Musical group" , "Group of Magi?" , "wise men?" .)