Plain English Meaning
A way of running two approaches into two close-together parallel runways at the same time. One plane flies straight in. The other flies a slightly angled approach so the two aircraft stay safely apart, then visually lines up with its own runway near the end.
Full Definition
An instrument approach procedure that allows two aircraft to fly approaches at the same time to closely spaced parallel runways whose centerlines are too close together for standard simultaneous parallel approaches. One aircraft flies a straight-in ILS or RNAV approach to one runway, while the other flies an offset approach (typically an LDA with glideslope or an offset RNAV) angled 2.5 to 3 degrees away from the first runway's final approach course. The offset keeps the aircraft laterally separated until the aircraft breaks visually and sidesteps to land on its own runway.