Definitions:

1. A form of non-verbal communication where emotions, thoughts or intentions are conveyed through movements or positions of the facial muscles, such as the eyebrows, eyes, nose, cheeks, lips, and overall facial shape. NOUN
   • Despite his calm words, his facial expression revealed his underlying frustration.
2. Is the movement or position of the muscles beneath the skin of the face. NOUN
   • Her facial expression changed from joy to surprise when she saw the unexpected guest.

Synonyms:

• expression
• facial gesture
• facial movement
• facial signal