Silhouettes

An illustrated outline filled in with a solid color(s), usually only black, and intended to represent the shape of an object without revealing any other visual details; a similar appearance produced when the object being viewed is situated in relative darkness with brighter lighting behind it; a profile portrait in black, such as a shadow appears to be.

"I could see a silhouette of a figure looking out from the window, but I couldn't tell if it was a man or a woman."

To represent by a silhouette; to project upon a background, so as to be like a silhouette.