1. In a bipolar transistor, the electrode toward which emitted current carriers travel. 2. In a Klystron, the final electrode toward which electrons migrate after passing through the buncher and catcher. 3. In an iconoscope, a cylindrical electrode around the circumference of the tube, which gathers and conducts away the electrons released by the mosaic. 4. The final (target) electrode in a backward-wave or traveling-wave tube. 5. A computer program segment that collates compiled segments so that they can be loaded into the computer.