N of n
The 'look' group
The noun refers to the way someone looks or what they say. The noun group after of indicates the feeling the person has or is expressing. This is a productive use: all nouns which refer to facial expressions and noises uttered by people can be used with this pattern.
cry expression look mask
With a sharp cry of horror, she drew back violently against the bedstead.
A look of surprise flickered across his face.