1. The boundary between Maryland and Pennsylvania; symbolic dividing line between North and South before the American Civil War
   - Mason-Dixon line, Mason and Dixon line

Type of: state boundary, state line

• institutionally
• institutor
• instroke
• instruct
• instruction
• instruction book
• instruction execution
• instruction manual
• instructional
• instructions
• instructive
• instructively
• instructor
• instructorship
• instructress
• instrument
• instrument flying
• instrument landing
• instrument of execution
• instrument of punishment
• instrument of torture
• instrument panel
• instrumental
• instrumental conditioning
• instrumental music