It is most definitely a diminutive of Ariel. Famous bearers include Ariel "Arik" Sharon, the former prime minister of Israel; Ariel "Arik" Benado, a footballer who plays for Maccabi Haifa; and Arik Einstein, a guitarist who has played with Red Hot Chilli Peppers, Gwen Stefani and many others.
― Anonymous User 12/20/2010
2
I think Arik isn't a diminutive of Ariel but of Erik or Eric.