Jones the architect checking daughter's colour (6)
I believe the answer is:
indigo
'colour' is the definition.
(I know that indigo is a dye)
'jones the architect checking daughter's' is the wordplay.
'jones the architect' becomes 'inigo' (I've seen this in another clue).
'checking' means one lot of letters goes inside another (check can mean to control or arrest).
'daughter' becomes 'd' (genealogical abbreviation).
'inigo' enclosing 'd' is 'INDIGO'.
(Other definitions for indigo that I've seen before include "Deep-blue dye or colour" , "Natural blue dye" , "Blue-violet colour" , "Blue-purple colour in spectrum" , "Tropical plant" .)