Before midday I leave to find companion (5)
I believe the answer is:
amigo
'companion' is the definition.
(thesaurus)
'before midday i leave' is the wordplay.
'before midday' becomes 'am'.
'leave' becomes 'go'.
'am'+'i'+'go'='AMIGO'
'to find' is the link.
(Other definitions for amigo that I've seen before include "Foreign ally" , "friend in Uruguay" , "China (in Spain's view)" , "A Spanish pal" , "friend from Barcelona" .)