Shed built for a short time last month
I believe the answer is:
moult
'shed built for' is the definition.
The definition suggests a singular noun which matches the answer.
'a short time last month' is the wordplay.
'a short time' becomes 'mo' (slang abbreviation for 'moment').
'last month' becomes 'ult' (short for 'last month' in correspondence).
'mo'+'ult'='MOULT'
Can you help me to learn more?
(Other definitions for moult that I've seen before include "shed down perhaps" , "Periodically lose old feathers etc." , "Of animal, shed hair" , "Shed old feathers/skin" , "Shed feathers, hair or skin" .)