Shortened version of "knackered". When you are so knackered you don't even have the strength to say "knackered" and can only go as far as "knacked".

Someone who is possessed by clout chasing. The original human is now gone and a demonic entity that feeds on clout is all that is left. An empty shell with no control of their actions, forced to blindly react to situations they think will bring them attention.

Sexual slang (U.K, East Midlands, South Yorkshire, Lancashire (localised) :When men brag to their mates about sex with a very attractive women.
EG:

"I can't believe I knacked her"?

Anecdotally lying or exaggerating popping a girls cherry.

E.G:

"I knacked her ya know?"

Or similarly gloating about "breaking in" or "destroying" a supposed virgin (slang for wild, kinky, hard or just passionate sex) a woman known to be classy, and/or hard-to-get (usually to other lads). Or anal sex with a women :

"I PROPER knacked her!"

Conventionally among friends being deliberately as innapropriate, forthcoming or sexist, common as possible by replacing: "Knacked her."

With: "knacked that"

1. To be scolded, told off(see bollocking).

2. To be in pain.