Translation guide
The English phrase "at once" has two main meanings: "immediately" and "simultaneously." This guide helps learners choose the right Japanese expression for each meaning, with natural examples and usage notes.
Expressing that something happens without delay, right now, or instantly.
The most common and versatile word for "immediately" or "right away." Used in casual and formal contexts.
すぐ行きます。
I'll go at once.
Formal and often used in official announcements, instructions, or written contexts. Stronger sense of urgency than すぐ.
Means "instantly" or "on the spot." Often used for reactions or decisions made without hesitation.
彼は即座に答えた。
He answered at once.
Implies doing something promptly, often with a sense of eagerness. Common in phrases like 早速ですが ("without further ado").
Expressing that two or more things happen at the same time.
すぐ is the everyday word for "immediately." 直ちに is formal and urgent, often used in commands or warnings. 即座に emphasizes an instant reaction, common in narratives.
English "at once" can mean either "immediately" or "simultaneously." In Japanese, these are expressed with different words. Using すぐ for "simultaneously" or 同時に for "immediately" will cause confusion.
すぐに終わります。
It will finish at once.
直ちに避難してください。
Evacuate at once.
早速ですが、始めましょう。
Let's begin at once.
The standard way to say "at the same time" or "simultaneously." Works in most contexts.
二人は同時に話し始めた。
They both started talking at once.
同時に二つのことはできない。
I can't do two things at once.
Often used when multiple actions or items are handled in one go, or when something happens all at once. Slightly more colloquial than 同時に.
一度に全部食べないで。
Don't eat everything at once.
一度にたくさんの人が来た。
Many people came at once.
Used when a group does something all together at the same moment, like a coordinated action.
生徒たちは一斉に立ち上がった。
The students stood up at once.