Saint missing a space trip arranged for each person (3,6)
I believe the answer is:
per capita
'for each person' is the definition.
(synonyms)
'saint missing a space trip arranged' is the wordplay.
'saint' becomes 's'.
'missing' suggests deleting specific letters.
'arranged' is an anagram indicator.
'a'+'space'+'trip'='aspacetrip'
'aspacetrip' with 's' removed is 'apacetrip'.
'apacetrip' anagrammed gives 'PER CAPITA'.
(Other definitions for per capita that I've seen before include "A head" , "apiece" , "For each person - in routine Latin phrase" .)