eyebrow dormer [ayh-brou dawr-mer]
a dormer having a roof that is an upwardly curved
continuation of the main roof plane.
source - http://dictionary.reference.com/browse/eyebrow
Eyebrow dormers add a bit of distinction to a building's façade while providing a "curvaceous way to get some light" and ventilation to an upper level space. These types of dormers are not new to the architectural scene. They have been around since medieval times, seen on thatch-roofed cottages. Henry Hobson Richardson, "the father of the Shingle style," pushed this design element into the architectural limelight in the late 1800s. These days, they can be seen on homes and buildings outside of just the Shingle style and can be designed in a variety of shapes and sizes.
Here are some examples of Visbeen Associates' designed eyebrow dormers...