Translation guide
The English word 'automatic' can describe devices that operate by themselves, actions done without thinking, or processes that happen as a natural consequence. This guide covers natural Japanese expressions for each meaning.
Describing a machine or system that works without human intervention.
The most common and direct translation for 'automatic' when referring to machines, devices, or systems that operate on their own.
このドアは自動で開きます。
This door opens automatically.
自動運転の車が増えている。
Cars with automatic driving are increasing.
A loanword from English, often used in product names or technical contexts. Less common in everyday speech than 自動.
このカメラにはオートマチックモードがあります。
This camera has an automatic mode.
Means 'fully automatic', emphasizing that no manual operation is needed at all. Often used for appliances like washing machines.
全自動洗濯機を買いました。
I bought a fully automatic washing machine.
Describing an action that is performed unconsciously or as a reflex, without deliberate thought.
Literally 'unconsciously', this is the most natural way to express that an action is automatic in the sense of being done without awareness.
彼は無意識に髪を触る癖がある。
He has a habit of automatically touching his hair.
無意識に返事をしてしまった。
I answered automatically without thinking.
Means 'reflexively', emphasizing a quick, automatic reaction like a reflex. Suitable for physical or immediate responses.
ボールが飛んできて、反射的に手が出た。
The ball came flying and my hand automatically went out.
Means 'naturally' or 'spontaneously'. Can be used when an action happens automatically as a natural result, without force.
練習を重ねると、体が自然に動くようになる。
With practice, your body will move automatically.
Describing a result or outcome that follows inevitably from a situation or action.
The adverbial form of 自動, used for processes that happen automatically as a built-in consequence, such as in rules or systems.
会員登録すると、自動的にポイントが付与されます。
When you register as a member, points are automatically awarded.
更新は自動的に行われます。
Updates are performed automatically.
Means 'as a natural consequence'. Used when an outcome is logically or inevitably automatic given the circumstances.
努力しなければ、当然の結果として失敗する。
If you don't make an effort, failure is automatic.
A conditional pattern meaning 'if... then automatically...'. Useful for explaining cause-and-effect automatic processes.
このボタンを押せば自動的に電源が切れます。
If you press this button, the power will automatically turn off.
Referring to a weapon that continues firing while the trigger is pressed.
Used as a prefix for firearms, e.g., 自動式拳銃 (automatic pistol).
自動式小銃が使用された。
An automatic rifle was used.
自動 (じどう) is the standard Japanese word for 'automatic' and is used in most everyday contexts. オートマチック is a loanword that appears in product names, technical specifications, or to give a modern feel, but it is less common in casual conversation. When in doubt, use 自動.
While 自動 is perfect for machines, using it to describe a person's automatic behavior (like breathing or habits) can sound unnatural. Instead, use 無意識に (unconsciously) or 反射的に (reflexively).
Also used in the context of firearms, often in technical or military jargon.
オートマチックピストル
automatic pistol