A reduced gas appliance (3)
I believe the answer is:
aga
'a reduced gas appliance' is the definition.
The definition suggests a singular noun which matches the answer.
'a reduced gas appliance' is the wordplay.
'reduced' suggests taking the first letters (the word is reduced to its first letter).
The first letters of 'gas appliance' is 'ga'.
'a'+'ga'='AGA'
Can you help me to learn more?
(Other definitions for aga that I've seen before include "Muslim title and cooking stove" , "Type of stove" , "Eastern leader" , "military leader" , "Chief officer" .)