Sweet line caught in couple’s song (6)
I believe the answer is:
dulcet
'sweet' is the definition.
(synonyms)
'line caught in couple's song' is the wordplay.
'line' becomes 'l' (used when specifying particular lines from a poem).
'caught' becomes 'c' (cricket abbreviation).
'in' indicates putting letters inside.
'couple's song' becomes 'duet' (I can't justify this - if you can you should believe this answer much more).
'l'+'c'='lc'
'lc' put into 'duet' is 'DULCET'.
Can you help me to learn more?
(Other definitions for dulcet that I've seen before include "Mellifluous, pleasing to the ear" , "Soft, sweet (tones)" , "Sweet, gentle (tones)" , "Soft and pleasant sounding" , "(Of sound) sweet and soothing" .)