1. Marks or lines made on two surfaces to show how they should be aligned or fitted together, typically used in manufacturing, assembly, or repair work.
Usage: Usually plural; technical/industrial term

Examples

• The mechanic used matchmarks on the driveshaft to ensure proper reassembly.
• Before disassembling the engine, the technician drew matchmarks on the timing cover.
• The two parts had matchmarks that helped us line them up correctly.
• Matchmarks on the suspension components prevented misalignment during installation.
• The factory applied matchmarks to guide customers in the assembly process.