Hold goose's tail, moving an egg (6)
I believe the answer is:
engage
'hold' is the definition.
(I've seen this before)
'goose's tail moving an egg' is the wordplay.
'tail' suggests the final letters.
'moving' indicates an anagram.
The last letter of 'goose' is 'e'.
'an'+'egg'='anegg'
'anegg' is an anagram of 'ngage'.
'e'+'ngage'='ENGAGE'
(Other definitions for engage that I've seen before include "Take into employment or occupy attention" , "Occupy (interest)" , "Pay to serve" , "Thief (rhyming slang)" , "Take into service or commit to marriage" .)