Introduction to star at home (4-2)
I believe the answer is:
lead-in
'introduction' is the definition.
(I've seen this before)
'star at home' is the subsidiary indication.
'star' becomes 'lead' ('lead' can be a synonym of 'star').
'at home' becomes 'in' ('in' can be similar in meaning to 'at home').
'lead'+'in'='leadin'
'to' is the link.
(Other definitions for lead-in that I've seen before include "Introduction to subject" , "Introduction, preamble" , "Introductory passage" .)