The ear emoji depicts a simple outline of a human ear.
Unicode: U+1F442
The ear emoji is often used to convey the act of listening or paying attention. It can also signify sound, music, or audio-related topics. Some people use it to indicate they've heard or acknowledged something.
"I'm all ð if you want to talk about your day."
"Turn up the volume, I can't hear the music ð"
"ð Got your message, I'll get back to you soon."