It means to fight - lots of male animals butt heads when they fight, such as Goats and Sheep and deer. You also hear the same term used: "butt heads" instead of "knock heads."
Knock on wood means you are hoping that it happens.
Entering a House - "Ko ko!" means "Knock knock!"
knock each other out
Knock on wood means you are hoping that it happens.
Knock out!
hey why are you so mean....... I'm not mean I'm a gymnast with a attitude!
you mean knock sensor
In the UK we would use the phrase 'Knock it off' to mean stop teasing/irritating me or stop what you doing.
knock
That depends on what you mean by 'knock'. knock as in ' faulter ' or ' critisize '
Duralast/Knock SensorFor your nissan Infiniti OEM 2206030p00
It means Go for it