一時に|いちどきにichidokini[3]nakadaka (mid-high)

1. adverbat the same time; at a time; at one time; simultaneously

• SynonymいっぺんにCasualDoing everything at once in a single action, or in an instant; more colloquial than 「一時に」.
• Synonym一度にいちどにNeutralDoing something in one action or all together; synonymous with 「一時に」 but the everyday, more commonly used choice.
• Related一気にいっきにNeutralFor doing something in one go without a break, or for a sudden dramatic change; more forceful than 「一時に」.
• Antonym徐々にじょじょにNeutralChanging slowly, little by little; the opposite of 「一時に」, which is about things happening all at once.
• AntonymだんだんNeutralRead 「だんだん」: changing little by little as time passes, stressing the step-by-step process; the exact opposite of 「一時に」. The jagged sense is a different word, 「ギザギザ」.

Use 「一時に」 for many things happening at once; it is slightly formal, more at home in written prose, as in 「一時に押し寄せる」. In everyday speech say 「一度に」 or 「一遍に」; for doing something in one go, 「一気に」. The opposites are 「徐々に」 and 「段々」.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 同おなじ時ときに、いっぺんに起おこることを表あらわす。