One bowled over by PM's address on good bit of news (6)
I believe the answer is:
tenpin
'one bowled over' is the definition.
I can't judge whether this defines the answer.
'pm's address on good bit of news' is the wordplay.
'pm's address' becomes 'ten' (the prime minister lives in No 10 Downing Street).
'on' means one lot of letters go next to another (in a down clue, letters appear on others).
'good' becomes 'pi' (old-fashioned term for pious).
'bit of' says to take the initial letters.
The first letter of 'news' is 'n'.
'ten'+'pi'+'n'='TENPIN'
'by' acts as a link.
Can you help me to learn more?
(Other definitions for tenpin that I've seen before include "Skittle" , "Type of bowling" , "Kind of indoor bowling like skittles" .)