On this day, Dec. 18, in hip-hop history...

2001: One of hip-hop's greatest rap feuds ever, Nas vs. JAY-Z goes down in history. After Jay released "Takeover," a diss track aimed at Nas and Prodigy of Mobb Deep off his sixth studio album, The Blueprint, the world waited for a response from the God's Son. He would later release "Ether," a response toward JAY-Z, which is off of his fifth studio album, Stillmatic.

Stillmatic—released in the wake of a series of commercially successful, yet critically panned LPs, 10 years ago—finally saw Nas find his footing between record sales and acclaim with "Ether" as a standout cut. "Ether" was monstrous, turning the hip-hop world upside down. He would say to The New York Times that he chose to name the song "Ether" because he wanted to burn Hov's spirit. ''I was told a long time ago, ghosts and spirits don't like the fumes from ether, and I just wanted to affect him with my weapon and get to his soul,'' Nas said. The song attacked every component of Hov at the time, from his street cred to selling out.

Nas' "Ether" continues to be mentioned by rappers as one of the top diss records and one of the most influential of all time in hip-hop. It has been referenced and sampled by artists since it was released back in December 2001. The word shortly after the song's release entered into hip-hop's vocabulary becoming a slang expression synonymous with ruthlessness.

See Best Rap Performance Nominees & Winners at the Grammys Over the Years