What is Lie-face?
1.
the most obvious look on your face that tells someone that you are lying. when everything on your face- every expression- says "hey, i'm a liar", then you are wearing your lie-face.
big sister: "you stole my shirt!"
little sister: (grinning when she says,) "no, i didn't."
big sister: "do you think i'm stupid? i know you did! i can totally tell you're lying! you have your lie-face on!"
See