The one thing you're perfect for or is perfect for you. A rushmore is the one thing that you're good at and should do it for the rest of your life. If your rushmore is a person, that's the person you should spend the rest of your life with. Example: She's my rushmore, Max.
RUSHMORE
Meaning of RUSHMORE in English
Slang English vocab. Английский сленговый словарь. 2012