1. the act or process of joining or connecting two things together
Usage: formal or technical; less common than 'coupling'
2. a pair or couple of things joined together
Usage: archaic or rare

Examples

• The couplement of the two railway cars was completed smoothly.
• The engineer oversaw the couplement of the mechanical parts.
• A successful couplement requires precise alignment of the components.
• The couplement of theory and practice is essential in engineering.
• They discussed the couplement of the two systems in the meeting.