What is "nearco"

Nearco (January 24, 1935 – June 27, 1957) was an Italian-bred Thoroughbred racehorse described by Thoroughbred Heritage as "one of the greatest racehorses of the Twentieth Century" and "one of the most important sires of the century." He was not only unbeaten, winning 14 races at distances from 5 furlongs (1,000m) to 1 mile 7 furlongs (3,000m), but also was the patriarch of the most dominant sire line in Thoroughbred history.