1The uppermost part of a person's or animal's body, containing the face and brain; the head. Most commonly read 'atama'.
自転車で転んで頭を強く打った。
I fell off my bicycle and hit my head hard.
帽子を忘れたので頭が日に焼けてしまった。
I forgot my hat, so my head got sunburned.
彼女は頭を下げて丁寧にお辞儀をした。
She bowed her head politely.
頭が痛いので早めに休ませてください。
My head hurts, so please let me rest early.
2Hair on one's head; a colloquial equivalent of 髪 (kami).
最近、頭が薄くなってきた気がする。
I feel like my hair has been thinning out lately.
彼は頭を真っ赤に染めている。
He has dyed his hair bright red.
久しぶりに頭を洗ってさっぱりした。
I washed my hair after a long while and felt refreshed.
3The mind, brains, or intellect — one's ability to think, judge, or remember. Often used in evaluations of people, as in 頭がいい (smart) or 頭が悪い (not smart). Limited to the reading 'atama'.
この問題を解くには頭を使わないといけない。
You have to use your head to solve this problem.
田中さんは本当に頭がいい人だ。
Tanaka is a really smart person.
寝不足で頭が働かない。
My brain isn't working because of lack of sleep.
怒らずに、頭を冷やしてから話そう。
Don't get angry — let's cool our heads before we talk.
4The leader, chief, or boss of a group or organization. When read 'kashira', it carries a traditional nuance of the head of a household, gang, or band.
盗賊団の頭がついに逮捕された。
The leader of the band of thieves was finally arrested.
「親分」と呼ばれるその男が一家の頭だ。
The man they call 'boss' is the head of the family.
お頭、我々はどうすればよいでしょうか。
Chief, what should we do?
5The top or tip of an object; the head of a nail, screw, pin, match, etc.
釘の頭をハンマーでしっかり打ち込んだ。
I drove the head of the nail in firmly with a hammer.
マッチの頭を擦って火をつけた。
I struck the head of the match to light it.
ネジの頭がつぶれて、ドライバーでは回せなくなった。
The head of the screw got stripped, so a screwdriver can no longer turn it.
6The beginning or start of something — the very first part, as in 月の頭 (the start of the month) or 話の頭 (the opening of a talk).
来月の頭に引っ越す予定です。
I plan to move at the beginning of next month.
話の頭で肝心なことを言っておくと分かりやすい。
It's easier to follow if you state the main point right at the start of your talk.
曲の頭から聴き直してみよう。
Let's listen to the song from the beginning again.
7A unit for counting people, used in the sense of 'one person' or 'per head'. Seen in expressions such as 頭数 (number of people) and 頭割り (splitting equally per person). Limited to the reading 'atama'.
会費は頭割りにして一人三千円にしよう。
Let's split the fee per head and make it three thousand yen each.
参加者の頭数を数えてから料理を注文する。
We'll count the number of participants before ordering the food.
8A colloquial abbreviation of 頭金 (atamakin) — the down payment or initial lump sum paid when buying something on loan or installment. Read 'atama'.
車を買うために頭を五十万円ほど用意した。
I put aside about five hundred thousand yen as a down payment for a car.
頭を多めに入れれば、月々の返済は楽になる。
The bigger the down payment, the easier the monthly installments become.
9A technical term for the top structural component (crown) of a kanji character. Read 'kashira'.
「花」という字の頭（かしら）は草冠（くさかんむり）である。
The top component (kashira) of the character 花 is the grass radical (kusakanmuri).
10In mahjong, a colloquial term for the pair of identical tiles (jantō) required to complete a winning hand. Read 'atama'.
和了するには頭と面子が四組必要だ。
To win in mahjong, you need a pair (head) and four melds.
字牌で頭を作ると役がつきやすい。
Making your pair from honor tiles tends to give you more scoring hands.