Roman (5)
(Other definitions for greco that I've seen before include "El .... was great Spanish painter of Greek origin" , "El ... Spanish painter born in Greece" .)
'roman' is the definition.
This is all the clue.
(Other definitions for latin that I've seen before include "Romantic language" , "a quarter of Parisians" , "ancient tongue" , "and 15 Down: Student area of Paris" , "Parent language of French,Romanian" .)
(Other definitions for numeral that I've seen before include "Symbol representing one or two, perhaps?" , "Symbol used to express quantity" , "Eg, 5, nine or 6301" , "Figure or symbol like '1', for example" , "Eg, two or seven" .)
'roman' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for catholic that I've seen before include "(Of tastes) wide-ranging" , "This religion lit coach up" , "Including a wide variety of things" , "of interest to all" , "Universal (church)" .)