The Sigma face is a face where while smiling you suck in your cheeks (Hey! Not those ones). You can nod your head and make some other faces while sucking in your cheeks. Some people call it the sigma face or TopG face.
In the movie 'American Psycho' you can see Patrick Bateman kinda doing it.
A council of gigachads. Notable members include gigachad himself, v1nce cuh, quandale dongle, and also me. I was added in for seeing morbius and minions: the rise of gru on the same day, as well as my mario kart skills. They scare me.
Basically when you upload something related to gigachad's and then your comment section gets spammed by " insert something related to equality -a truegigachad
Gigachad sez: On Urban Dictionary, you don't have to be a real dummy and post inappropriate definitions about stuff. Think about your little brother and also if your family sees your definition on the site. You don't have to try and be someone else you're not by writing retardish definitions that may appear funny but in reality are extremely stupid and gross. Be yourself. Don't try to appear funny to other people, just be your normal self.
The Gigachad message is explained above. By writing normal definitions, you are a real chad and not a jerkoff virgin.