Interlock \In`ter*lock"\, v. i. To unite, embrace, communicate with, or flow into, one another; to be connected in one system; to lock into one another; to interlace firmly.
Interlock \In`ter*lock"\, v. t. 1. To unite by locking or linking together; to secure in place by mutual fastening.
My lady with her fingers interlocked. --Tennyson.
2. To connect together so that the parts work together as a coordinated unit; to connect as a single system. [PJC]
The latter often call for forming a scrum, in which eight players from each side interlock in a pack and struggle mightily for control of the ball.