Jackface

A term used to describe the contorted facial expression Matthew Fox's character, "Jack Shephard", makes when he is angry, yelling, or just plain acting crazy on the television show "Lost"

One whose face is of Jackish quality.

1. A good insult for someone when you're bored of the standard insults and you want to try something new.

2. A term used to describe someone who is being a jackface.

A moron, a dumbass, someone who is oblivious to the fact that there mere presence makes others want to vomit.

A sly way to insult someone without them knowing it.

Someone who thinks they are cool but just ends up making a fool of themselves.

The Ultimate Jackface is a meme from the Lostpedia Forums in which the member JoeyeoJ discovered a moment in the penultimate Lost episode "What They Died For" in which Jack Shephard, played by Matthew Fox, looks directly at the camera. The original poster continued to post various pictures, including Lost screenshots, in which the face is inserted into the shot. Sometimes text is included and sometimes they are in a multi-panel form like a Dinosaur Hed, a similar meme from the Lostpedia Forums. Other members of the forum have also taken to making these. The name references the various faces that Matthew Fox makes while playing the character of Jack, which have become known as Jackfaces.

This is a polite way to between SmartASS and JackAss to be used in public area where you need to watch your language