outline, lineation -- (the line that appears to bound an object)
outline, synopsis, abstract, precis -- (a sketchy summary of the main points of an argument or theory)
outline, schema, scheme -- (a schematic or preliminary plan)
Overview of verb outline
The verb outline has 3 senses
sketch, outline, adumbrate -- (describe roughly or briefly or give the main points or summary of; "sketch the outline of the book"; "outline his ideas")
draft, outline -- (draw up an outline or sketch for something; "draft a speech")