Definitions

1. adjective

resistant to or not affected by a person’s smile, especially in terms of a material or object being able to withstand or resist damage caused by a smile.

“The smileproof glass on her phone case allowed it to withstand accidental drops.”

2. adjective

designed to be resistant to or not affected by a person’s smile.

“The smileproof phone case was a great purchase for someone who often smiled while using their phone.”