Snxl

Derived from Xhosa term "Andisenxile" which means I am so drunk. It is mostly used by girls on social to indicate that they've had too much to drink.
Can also be spelled as senxl.

Yho snxl kamnandi mntkbw.

PK

Pastor's Kid or Preacher's Kid.
There's a stereotype that they grow up in very strict households but once they get their "freedom", they become very rachet.

The way she dances with that Savanna, you wouldn't believe that she is a PK.

Nyisa

Show you flames or to literally make you shit yourself.

Mjolo will nyisa you. 

Afrikaans

Afrikaans is a Low Franconian West Germanic language descended from Dutch and spoken mainly in South Africa and Namibia. 

I would rather do an unprepared speech in Afrikaans that ukujola with you. 

Zaka

A kasi word that is used to refer to money. 

I just need some zaka to buy the braai meat and all will be well

Skaftin

A lunchbox; a portable, usually plastic, container for food, such as Tupperware.
Also occurs as skaftien, skhafthin

Plase bring a skaftin, I want to put my leftovers. 

Chillas

Relaxing, socialising with friends over drinks and sometimes some braai meat at someone’s home, tavern, club or at a pub.

I'm planning a chillas this coming weekend at my place.

Moer

To beat someone to a pulp.

Can also be a swear word in Afrikaans

I will moer you.

Mdidi

A vulgar or explicit way to say butt or ass.

Do not say this to anyone or you will be moered. 

You are mad, mdidi wakho. 

Jola

This depends on the context. Jola can be someone's clan name if you are Xhosa. 

It can also mean dating, see ukujola or mjolo.

NdinguJola, Mphankomo...