What does "straight face" mean?

A face that is expressionless, especially not laughing.

What is a synonym for "straight face"?

Common synonyms include: anesthesia, autism, catatonia, chill, chilliness, cold blood.

Pronounced //ˌstɹeɪt ˈfeɪs//.

/ˌstɹeɪt ˈfeɪs/ noun

noun ·Uncommon ·Advanced level

Noun

1
A face that is expressionless, especially not laughing. idiomatic
"I don't think I could recite "Peter Piper" quickly ten times with a straight face."
2
a serious facial expression giving no evidence of interest or amusement wordnet

"I don't think I could recite "Peter Piper" quickly ten times with a straight face."