1The basic interrogative pronoun 'what', used to ask about things, content, or information (何を, 何が, 何の…), and with particles as in 何か ('something'). Read なん before だ/で/の/と and counters (see 何/なん).
これ、何ていう料理ですか。
What is this dish called?
週末は何をするつもりですか。
What are you planning to do this weekend?
おなかすいた。何かおいしいものが食べたいな。
I'm hungry. I want to eat something tasty.
鞄の中に何が入っているの。
What's in the bag?
「料理の中で何が一番好き？」「うーん、難しい質問だね。」
"What food do you like best?" "Hmm, tough question."
2A vague placeholder for something both speaker and listener already know — 'you-know-what / that thing'. Casual, conversational.
ねえ、この前話してた何、あれその後どうなった。
Hey, that you-know-what we talked about the other day — how did it turn out?
冷蔵庫に何、ほら昨日買ってきた物あるから食べていいよ。
There's the you-know-what in the fridge — the thing I bought yesterday — feel free to eat it.
3A filler slipped in when a name or word won't come to mind — 'whatsit / what's-his-name'. Used in forms like 何とか, 何さん, 何だっけ.
田中さんの隣の、何さんだっけ、あの人最近見ないね。
Tanaka's neighbor, what's-his-name — I haven't seen that person lately.
何とかっていう新しいアプリ、もう試してみた。
Have you tried that whatsit new app yet?
4A crude, colloquial euphemism for the penis, used to avoid the direct word. Usually written in kana as ナニ.
医者に「ナニの具合はどうですか」と遠回しに聞かれて、少し気まずかった。
The doctor asked indirectly "How's your, er, you-know-what?" and it was a bit awkward.
5Adverbial use with a negative, meaning 'not at all' or 'cannot really (say/feel)'. Mostly in the pattern 何とも〜ない.
結果については、今の段階では何とも言えません。
I can't say anything at all about the outcome at this stage.
あとで謝られたが、私はもう何とも思っていない。
He apologized later, but I don't feel anything about it at all anymore.
6Interjection 'what?! / huh?' expressing surprise or asking for something to be repeated.
「彼、来月で会社辞めるって。」「何!? 本当に。」
"He says he's quitting the company next month." "What?! Really?"
何？今、外で大きな音がしなかった。
Huh? Didn't you just hear a loud noise outside?
7Interjection expressing anger or irritation — 'hey! / come on! / what's that?'. Used to push back at someone's words or attitude.
何だよ、急に怒り出して。理由をちゃんと言ってよ。
What's with you, suddenly blowing up? Tell me the reason properly.
何、その言い方。もう少し言葉を選びなよ。
What's with that way of speaking? Watch your words a bit.
8Interjection that lightly waves away someone's worry or apology — 'oh, it's nothing; don't worry about it'.
「迷惑かけて本当にごめん。」「何、気にしないで。困ったときはお互いさまだよ。」
"I'm really sorry for the trouble." "Oh, don't worry about it. We help each other when we're in a bind."
何、こんなの大したことないよ。すぐ直せるから安心して。
Oh, this is nothing. I can fix it right away, so don't worry.