表情 (biǎoqíng) means "facial expression." It refers to the look on someone's face, and in modern usage also refers to emoticons or memes, as in 表情包 (emoji/sticker pack).
她脸上的表情看起来很紧张。
Tā liǎn shàng de biǎoqíng kàn qǐlái hěn jǐnzhāng.
The expression on her face looked very nervous.
他发了一个搞笑的表情包给我。
Tā fā le yí gè gǎoxiào de biǎoqíng bāo gěi wǒ.
He sent me a funny emoji sticker.
从你的表情就能看出你在说谎。
Cóng nǐ de biǎoqíng jiù néng kàn chū nǐ zài shuōhuǎng.
I can tell from your expression that you're lying.