Wow some vacuous fools (5)
I believe the answer is:
geese
'fools' is the definition.
(goose can mean a foolish person)
'wow some vacuous' is the wordplay.
'wow' becomes 'gee' (I've seen this in another clue).
'vacuous' suggests removing the centre.
'some' with its centre taken out is 'se'.
'gee'+'se'='GEESE'
(Other definitions for geese that I've seen before include "Edible water birds" , "Sixth day of Christmas gift" , "They're seen in a gaggle" , "Grey-lags" , "Proverbially silly birds" .)