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amicus usque ad aras

American  
[ah-mee-koos oos-kwe ahd ah-rahs, uh-mahy-kuhs uhs-kwee ad ey-ras, uh-mee-] / ɑˈmi kʊs ˈʊs kwɛ ɑd ˈɑ rɑs, əˈmaɪ kəs ˈʌs kwi æd ˈeɪ ræs, əˈmi- /

noun

Latin.
  1. a friend to the last degree.