ありがとう (arigatō) means “thank you.” It is a familiar expression; ありがとうございます is the polite form. In modern Japanese, ありがとう is an interjection, historically derived from the adjective ありがたい.
also arigato / arigatō / 有り難う / ありがとうございます
thank you · thanks
Sentences
ありがとう · the casual form
casual。
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本当に
ほんとうに ［5,0］
really; truly
adverb · 本当 truth ＋ に; intensifies what follows
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ありがとう
ありがとう ［2］
thank you
interjection · historically derived from 有り難く through ウ音便
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Thank you, really.
ありがとうございます · the polite form
polite、。
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先生
せんせい ［3］
teacher
noun · also the way you address them, with no さん
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ありがとう
ありがとう ［2］
thank you
interjection · ございます makes this a polite expression
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ございます
ございます
polite ending
polite form used here in the established expression of thanks
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Thank you, teacher.
ありがとうございました · the past
polite past。
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昨日
きのう ［2］
yesterday
noun · used adverbially, and here topicalised by は
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は
は
as for — the topic
particle · written は, read わ
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ありがとう
ありがとう ［2］
thank you
interjection · unchanged; the tense lives in what follows
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ございました
ございました
polite ending — past
past of ございます · here thanking for help received yesterday
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Thank you for yesterday.
〜てくれてありがとう · thanking for an act
casual。
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手伝って
てつだって
help — て-form
て-form of 手伝う · joins to くれる to make it a favour received
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くれて
くれて
did it for me — て-form
て-form of くれる · marks the favour as done toward the speaker
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ありがとう
ありがとう ［2］
thank you
interjection · the whole clause in front says what for
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Thanks for helping me out.
有り難い · the adjective itself
polite。
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有り難い
ありがたい ［4］
welcome; much appreciated
i-adjective · 有る to exist ＋ 難い difficult — rare, and so valued
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話
はなし ［3］
offer; proposition
noun · literally a talk, and by extension the deal being talked about
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です
です
polite ending
copula · the polite full stop on a noun phrase
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ね
ね
isn't it
sentence-final particle · invites agreement about the offer
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That's a very welcome offer.
Forms
ありがとう
Familiar, often with friends and family. ございます makes the expression polite; relationship and context matter more than age alone.
ありがとう＋ございます
The standard polite form, present tense. Use it for a favour in progress or just done, and for anyone you would use です with.
ありがとう＋ございました
Often used to look back on an occasion: 今日はありがとうございました at the end of a lesson, meeting or visit. This is a common pattern, not an exclusive rule.
Verb て-form ＋ くれて＋ありがとう
Thanking for a specific act: 手伝ってくれてありがとう. くれて marks the favour as done toward you; polite it becomes 〜ていただきありがとうございます.
Meaning
In modern Japanese, ありがとう is an interjection meaning “thank you.” Its origin is adjectival: 有り難く, a form of 有り難い, underwent the sound change called ウ音便 to become 有り難う. The historical derivation and the word’s modern grammatical category are different things.
有り難い is the adjective. Dictionaries record both the older sense “rare” and the familiar meanings “welcome” or “appreciated.” That history helps explain the expression, but someone saying ありがとう today is thanking you, not literally assessing how rare your kindness is.
ありがとうございます is the polite form. ありがとうございました often looks back on a completed occasion or help already received. For example, the Tokyo University of Foreign Studies dialogue uses the first after a teacher stamps a document and the second when returning a borrowed book. These are useful patterns, not a rule that every completed favour requires the past form.
Choose a reply that fits the exchange. どういたしまして is a conventional polite response to thanks. いえいえ can gently play down the favour; こちらこそ returns the thanks when you also have something to thank the other person for.
Inside the word
The kanji combine 有る (exist) with 難い (difficult). Keep the historical “rare” sense separate from the everyday adjective meaning “welcome” or “appreciated,” and from the interjection ありがとう.
The dictionary identifies this as ウ音便, a historical sound change. It explains the origin of this established expression; it is not an instruction to replace く with う in every modern adjective.
Kanjium records 有り難う as accent ［2］ and 有り難い as ［4］. For ありがとう, the citation-form pattern starts low on あ, rises on り, then drops. Connected speech and expressive intonation can change how the phrase sounds.
Watch out
ありがとう is familiar and suits many exchanges with friends or family. ありがとうございます is a safer default with strangers and in formal situations. Relationship and context matter; age alone does not decide the form.
ありがとうございました often looks back on a finished lesson, visit or favour. ありがとうございます can also thank someone immediately after an act. Do not infer that the present form always means the help is unfinished.
It is a conventional reply meaning “you’re welcome.” Alternatives include いえいえ and, when returning the thanks, こちらこそ. There is no single reply required in every relationship.
The standard spelling is ありがとう, with う. Casual messages may shorten or stretch words for effect; those spellings are not the standard form to learn first.
Also asked
It means “thank you.” It is an interjection; its historical source is a form of the adjective 有り難い (ありがたい).
ありがとう is familiar; ありがとうございます is polite. Use the polite form as a default with strangers or in formal situations, and choose according to your relationship and the occasion.
It often looks back on a completed occasion, such as a lesson or visit, or help received earlier. ありがとうございます is also natural immediately after receiving help; the choice is not determined by completion alone.
どうも can be a brief thanks on its own. In どうもありがとうございます it strengthens the expression of gratitude. Use a fuller phrase when you want to make your thanks explicit and polite.
どういたしまして is a conventional “you’re welcome.” いえいえ can play down the favour, and こちらこそ returns the thanks. Choose a reply that fits what happened.
ありがとう has a long final o sound. Arigatou preserves the kana spelling; arigatō marks the long vowel with a macron. Arigato is a common English spelling, but it leaves the vowel length unmarked.
References
Digital Daijisen: 有難う (via Kotobank) — Modern classification as an interjection and derivation from 有り難く through ウ音便.
Digital Daijisen: 有難い (via Kotobank) — The adjective’s rare, welcome and thankful senses.
Tokyo University of Foreign Studies: expressing thanks — A dialogue contrasting thanks after receiving help with thanks when returning a book, and the response いえいえ.
Digital Daijisen: 如何致しまして (via Kotobank) — A conventional polite response to gratitude, apology or praise.
Kanjium pitch-accent data — Uros O. — Dictionary-form accent entries for 有り難う [2] and 有り難い [4]; not a guarantee of every spoken intonation.
Nearby
the apology that is doing duty as thanks
お疲れ様 vs ご苦労様otsukaresama · gokurousamathe other phrase that closes a day
いただきますitadakimasuanother set phrase with a live verb in it
遠慮enryothe holding back that shapes what you accept
こんにちはkonnichiwaanother greeting that is half a sentence
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