Amicus usque ad aras is a Latin phrase usually translated into English as "a friend as far as to the altar," "a life-long partner," or "a friend to the very end."[1]
The plural of amicus is amici leading to a separate usage of amici usque ad aras.[2]
A song of the same name dates to the defunct Yale University Greek organization Phi Theta Psi in 1864.[3] The tune used comes from the traditional song "Annie Lisle".
Phi Kappa Psi fraternity's song "Amici" includes the phrase "amici usque ad aras" and appears to be based on the Yale tune.[4]
The phrase also appears in the fraternity of Alpha Chi Rho's song "Amici" and the anthem song of 'Le Bourdon' of the 'Deltsch Studenten Corps' "Our Strong Bands".
This phrase has also been used by two members of the K-pop group ATEEZ. Choi San and Jung Woo-young use this phrase to show the special relationship that they have. Both of them like to describe each other as ‘soulmates’, each others’ half of the other and alter ego. Both of them also have a matching tattoo with this phrase. Woo-young has the tattoo on his right thigh and San has it on the same spot.