According to the definition, a grimace is „a deliberately strange, bizarre, comical or ugly facial expression,“ which already gives you a certain idea. However, the Chinese word for „grimacing“ sums up this facial muscle play even more aptly. There it is called 扮鬼脸 bàn guǐliǎn or 做鬼脸 zuò guǐliǎn „to put on a ghost face“ or „to make a ghost face“. Who would have thought it, by the way: Children learn to consciously control their facial expressions by making faces.