Got up to “Are very big inside” (5)
I believe the answer is:
arose
'got up' is the definition.
(I've seen this before)
'are very big inside' is the wordplay.
'very big' becomes 'os' (abbreviation for outsize).
'inside' means one lot of letters goes inside another.
'are' enclosing 'os' is 'AROSE'.
'to' is the link.
(Other definitions for arose that I've seen before include "appeared" , "Occurred; stood up" , "Issued" , "Got out of bed" , "Happened" .)