very informal!

something that you say after repeating something someone has just said, in order to show that you do not believe it.

'She's offering good money.' 'Good money, my arse! I can't feed my kids on that!'

• knock the tar out of
• knock the tar out of someone
• knock up
• knock wood
• knock yourself out
• knock your socks off
• know-all
• know a thing or two
• know backwards
• know backwards and forwards
• know beans about
• know beans about something
• know best
• know better
• know better than to
• know better than to do something
• know by heart
• know by sight
• know different
• know from Adam
• know if are coming or going
• know if you are coming or going
• know inside out
• know like the back of hand
• know like the back of your hand