See about, say, dedicated lines (5)
I believe the answer is:
elegy
'dedicated lines' is the definition.
(lines of poetry dedicated to someone)
'see about say' is the wordplay.
'see' becomes 'Ely' (see is a place with a cathedral - e.g. Ely).
'about' means one lot of letters goes inside another.
'say' becomes 'eg' (short for 'exempli gratia', 'for example' in Latin).
'ely' placed around 'eg' is 'ELEGY'.
(Other definitions for elegy that I've seen before include "Sad words" , "that may be on the dead" , "Poem lamenting the dead" , "Lines written by poet" , "Work of poet" .)