Study origins of every blue star (5)
I believe the answer is:
deneb
'star' is the definition.
(star of the constellation Cygnus)
'study origins of every blue' is the wordplay.
'study' becomes 'den' (term for a study or office).
'origins of' says to take the initial letters.
The initial letters of 'every blue' is 'eb'.
'den'+'eb'='DENEB'
(Other definitions for deneb that I've seen before include "Bright star; be end (anag.)" , "Bright star in Cygnus" , "First magnitude star in Cygnus" , "The star Alpha Cygni" , "Be Ned (anag) - brightest star in Cygnus" .)