To fill cracks or gaps in a structure (especially between logs in a log building) with mortar, caulking, or other material; to perform the process known as chinking.
2.
USUKGlobaloffensivevulgarslang
A highly derogatory and offensive expression meaning to silence or shut someone up, formed by combining the racial slur "chink" with the particle "up"; used as an insult or command to silence a person.