Female experts declare it spares one's blushes (4-5)
I believe the answer is:
face-saver
'it spares one's blushes' is the definition.
The definition suggests a singular noun which matches the answer.
'female experts declare' is the wordplay.
'female' becomes 'f' (abbreviation).
'experts' becomes 'aces' (ace is a kind of expert).
'declare' becomes 'aver' (averring is a kind of declaring).
'f'+'aces'+'aver'='FACE-SAVER'
Can you help me to learn more?
(Other definitions for face-saver that I've seen before include "Preserver of one's dignity" , "Something that maintains one's dignity" .)