Teams up every so often to produce large flyer? No! (3)
I believe the answer is:
emu
'produce large flyer? no' is the definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
'teams up every so often' is the wordplay.
'every so often' indicates alternate letters.
'teams'+'up'='teamsup'
The alternating letters of 'teamsup' are 'EMU'.
'to' is the link.
Can you help me to learn more?
(Other definitions for emu that I've seen before include "Physics unit" , "Large Australian flightless bird" , "Ostrich-like bird" , "Australian running bird." , "Extinct bird" .)