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もちろん
mochiron
of course
A: 明日、会議に出席しますか？ B: もちろんです！
A: Will you attend the meeting tomorrow? B: Of course!
informal
used to agree with a suggestion or request; to indicate something is obvious or expected
もちろん、手伝うよ。
Of course, I'll help.
A: コーヒー飲む？ B: もちろん！
A: Do you want coffee? B: Of course!
Often used in casual conversation. Can be softened with です (もちろんです) for politeness.
formal
without a doubt; certainly; definitely
もちろん、その件については検討します。
Certainly, we will consider that matter.
More formal than the casual usage, often used in business or official contexts.
Pro Tip
Politeness levels
In formal settings, append です (もちろんです) or ございます (もちろんございます) to sound more polite. In casual speech, simply use もちろん.
Gold Rule
Agreement marker
Use もちろん to strongly agree with a suggestion or to emphasize that something is obvious. Avoid using it in negative contexts.
Word Origin
From 物 (thing) + 知る (to know), originally meaning 'it goes without saying' or 'obviously.' The modern usage evolved from the shortened form of 物知り (monoshiri, 'know-it-all') in the Edo period, where it took on the sense of 'naturally' or 'as expected.'
Usage Notes
Used in both spoken and written Japanese. In formal writing, もちろん is often followed by です or ございます for politeness. In casual speech, it can stand alone. Overuse may sound overly enthusiastic.
Word Breakdown
物
thing
root知る
to know
root和英辞典