tariki 

A Japanese Pure Land term derived from the Chinese term t'a li meaning ‘other-power’. This refers to the power of Amitābha Buddha that supports and empowers the Pure Land devotee's practice. In Japanese Pure Land thought, tariki came to be seen as the only effective power that could save the practitioner; ‘self-power’ (jiriki) was seen as arrogant and useless.

A Dictionary of Buddhism, Oxford University Press, 2003, 2004 (which is available in electronic version from answer.com)