Magnetic lasso tool
From The Glossary of Digital Photography
A tool in Photoshop, similar to the lasso tool, used to make selections freehand within an image. As the user draws with the lasso tool and the mouse, the line created will snap to the nearest, strongest existing line. A user can outline an object simply by drawing near the edge; the tool snaps to the edge of the object as if it were magnetic. The magnetic lasso tool is similar to the magnetic pen tool. The main difference is that, with the magnetic pen tool, the user is drawing, or creating, a vector path. With the magnetic lasso tool, the user is selecting an area within an image. See also magnetic pen tool
