What is the meaning of Scowl?

The wrinkling of the brows or face in frowning; the expression of displeasure, sullenness, or discontent in the countenance; an angry frown.

Gloom; dark or threatening aspect.

To wrinkle the brows, as in frowning or displeasure; to put on a frowning look; to look sour, sullen, severe, or angry.

To look gloomy, dark, or threatening; to lower.

To look at or repel with a scowl or a frown.

To express by a scowl.

Old workings of iron ore.

Source: wiktionary.org