handshake

noun

1. a gripping and shaking of right hands by two individuals, as to symbolize greeting, congratulation, agreement, or farewell.
2. Also hand·shak·ing. Computers. an exchange of predetermined signals between a computer and a peripheral device or another computer, made when a connection is initially established or at intervals during data transmission, in order to assure proper synchronization.

noun

1. the act of grasping and shaking a person’s hand, as when being introduced or agreeing on a deal