Meaning

• A line marking the boundary of an object figure.

• The outer shape of an object or figure.

• A sketch or drawing in which objects are delineated in contours without shading.

• A general description of some subject.

• A statement summarizing the important points of a text.

• A preliminary plan for a project.

  "the outline of a speech"

• (film industry) A prose telling of a story intended to be turned into a screenplay; generally longer and more detailed than a treatment.

• A setline or trotline.

Meaning

• To draw an outline of.

• To summarize.

  "Wikipedia items featuring books usually outline them after giving their background."