ありがとう

有り難し, read ari-gatashi in older Japanese, is the source of ありがとう. The parts are 有り, to exist, and 難し, difficult, so the adjective first meant rare or hard to exist. Kotobank's Digital Daijisen links 有難 to the adjective ありがたし, and Nihon Kokugo Daijiten gives 源氏物語, dated around 1001-1014, as an early example of the stem ありがた. In medieval Japanese, the meaning moved from rarity to a feeling of awe or gratitude toward a benefit, authority, or favor. Nihon Kokugo Daijiten records ありがたう候 in the Noh text 松風 around 1423, with the polite auxiliary 候 in formal speech of Muromachi usage. The sound change is ウ音便: ありがたく becomes ありがたう, and in modern spelling and speech it becomes ありがとう. Related forms include ありがたい, ありがとうございます, and 有難迷惑. Modern ありがとう is a fixed thanks expression, while the older adjective ありがたい still keeps wider meanings: welcome, appreciated, rare, or even undeserved. English thank you focuses on the act of thanking; Japanese ありがとう comes from judging the act or favor as hard to get. Example: お時間をいただき、ありがとうございます means thank you for your time, with ございます adding politeness.