Meaning 1 ►▼
1) a home run in baseball with the bases loaded (on all bases); 4 runs scored. 2) in tennis: the player wins all four tennis opens: the French, Wimbledon, Australian and the U.S. 3) in the card game, bridge, when a player takes all 13 tricks.
Rafael Nadal won 14 and lost 6 grand slam tournaments.
Meaning 2 ►▼
A super win
The Republicans scored a home run in the 1952 election when Eisenhower ran for President. The Republicans won both the Senate and the House.
The original meaning may have come from baseball.