Grub to provide food and support (11)
I believe the answer is:
caterpillar
'grub' is the definition.
(thesaurus)
'provide food and support' is the wordplay.
'provide food' becomes 'cater' (I've seen this before).
'and' means one lot of letters go next to another.
'support' becomes 'pillar' (pillar is a kind of support**).
'cater'+'pillar'='CATERPILLAR'
'to' acts as a link.
(Other definitions for caterpillar that I've seen before include "future monarch, perhaps" , "potential beauty?" , "Butterfly/moth larva" , "Lepidopteran larva" , "8 17" .)