Blunder on live programme's finale leading to buzzer (9)
I believe the answer is:
bumblebee
'buzzer' is the definition.
(something which buzzes)
'blunder on live programme's finale' is the wordplay.
'blunder on' becomes 'bumble' (I can't explain this - if you can you should believe this answer much more).
'live' becomes 'be' (synonyms).
'finale' indicates one should take the final letters.
The last letter of 'programme' is 'e'.
'bumble'+'be'+'e'='BUMBLEBEE'
'leading to' is the link.
Can you help me to learn more?
(Other definitions for bumblebee that I've seen before include "Large furry flying insect" , "social worker" , "Striped buzzer" .)
