Circular sulcus of insula in the context of "Operculum (brain)"

In human brain anatomy, an operculum (Latin, meaning "little lid") (pl.: opercula), may refer to the frontal, temporal, or parietal operculum, which together cover the insula as the opercula of insula. It can also refer to the occipital operculum, part of the occipital lobe.

The insular lobe is a portion of the cerebral cortex that has invaginated to lie deep within the lateral sulcus. It sits like an island (the meaning of insular) almost surrounded by the groove of the circular sulcus and covered over and obscured by the insular opercula.