ありがとう

Taken apart

No breakdown is shown for this word: Wiktionary's text for it doesn't give a split that spells the word and joins to its reading, and any other split would be a guess.

In a sentence

We don't have the data for this section. The pinned Tatoeba export has no sentence with a translation that uses this word and passes our filter.

What Wiktionary says

Quoted line by line from Wiktionary's Etymology section for this reading, taken from one dated dump so it can't change underneath us. Nothing below is paraphrased.

• “Phonetic shift: /ariɡataku/ → /ariɡatau/ → /ariɡatoː/.”
• “From ありがたく (arigataku), the adverbial form of Old Japanese and Classical Japanese adjective ありがたし (arigatashi, modern ありがたい arigatai, “grateful, thankful; welcome”), from 有り (ari, the 連用形 (ren'yōkei, continuative or stem form) of verb 有る aru, “to exist, to be”) + 難し (katashi, “hard, difficult”, 難い katai in modern Japanese). The katashi changes to gatashi as an instance of rendaku (連濁).”
• “Modern Japanese -i adjectives formerly ended in -ki for the attributive form. This medial /k/ dropped out during the Muromachi period, both for the attributive form (-ki becoming -i) and for the adverbial form (-ku becoming -u). However, the adverbial form reverted to -ku thereafter for most words, with the -u ending persisting in certain everyday set expressions, such as arigatō, おはよう (ohayō), or おめでとう (omedetō), and in hyper-formal speech.”
• “Arigatashi is first attested in the oldest literature of the 8th century. It originally meant “difficult to exist, hard to be”, shifting to “rare, special”, and then to “welcome, thankful, nice to have” by some time in the 15th century. This sense is still in use:”
• “: この天(てん)気(き)はありがたいね。 ― Kono tenki wa arigatai ne. ― This weather sure is welcome (literally, “This weather sure is hard to come by”)”
• “The similarity to Portuguese obrigado (“thank you”) is purely coincidental; the Portuguese first arrived in Japan in 1543, well over a century after citations expressing gratitude are found.”

Source: Wiktionary: ありがとう (dump of 2026-09-02), available under CC BY-SA 4.0. Reading, meaning and part of speech from JMdict, and kanji readings from KANJIDIC2 (EDRDG).

What the labels mean

和語 Native Japanese

Words that were already Japanese before Chinese vocabulary arrived — usually written with kun'yomi and often short.

Rendaku

The first sound of the second part voices when two native words join (kami → -gami).

Sound change

The pronunciation shifted over the centuries.