即刻|そっこくsokkoku[0]heiban (flat)

1. noun, adverbimmediately; at once; instantly
   かんかんに怒おこった社員しゃいんは、即刻そっこく会社かいしゃを辞やめた。↗

   The outraged employee resigned at once.

• Synonym直ちにただちにNeutralMeans 'at once' but is mostly used in instructions and official notices, as in 「直ちに避難」; more common than 「即刻」.
• SynonymすぐにNeutralThe everyday default for 'right away'; 「即刻」 is more formal and stern.
• Synonym即座にそくざにNeutralStresses an immediate, on-the-spot response, as in 「即座に答える」.
• SynonymすぐNeutralThe most common colloquial choice for 'soon, right away'; it also means 'very near' or 'easily', senses 「即刻」 does not have.
• SynonymすぐさまNeutralMeans 'immediately, right away'; slightly more written than 「すぐ」 but less solemn than 「即刻」.
• SynonymとっさにNeutralFor split-second reactions with no time to think, as in 「咄嗟に身をかわす」 or 「咄嗟に判断する」.
• Synonym即時そくじNeutralMeans 'immediate, real-time', as in 「即時払い」; mostly modifies nouns, while 「即刻」 is an adverb modifying actions.
• SynonymたちまちNeutralMeans 'in an instant', as in 「たちまち売り切れる」; stresses a sudden change of state.
• Synonym早速さっそくNeutralMeans 'without delay' in getting started, as in 「早速始める」; stresses positive, willing action.
• SynonymすかさずNeutralMeans 'without a moment's hesitation, right after', as in 「すかさず反論する」; stresses seizing the moment.
• SynonymたちどころにNeutral'On the spot, at once', as in 「立ちどころに反論する」 or 「立ちどころに治る」; stresses instant effect, while 「即刻」 is more solemn and modifies the action itself.
• Synonym直様じきさまNeutralMeans 'at once, on the spot' but is dated and rare today; say 「すぐに」 in daily conversation.
• Synonym時を移さずときをうつさずNeutralA written phrase meaning 'without losing a moment'; in daily speech use 「すぐに」.
• RelatedやにわにNeutralMeans 'suddenly, abruptly', as in 「やにわに立ち上がる」; stresses the suddenness rather than mere speed.
• Related即そくNeutralA terse one-character adverb for 'at once', as in 「即入院」; it also means 'namely'. 「即刻」 is more solemn.
• Antonym後日ごじつNeutralAntonym: 'later, another day', as in 「後日連絡します」 — the opposite of doing something 「即刻」.
• Antonym後刻ごこくNeutralAntonym: 'later on', a somewhat formal word; the opposite of 'at once'.

Use 「即刻」 for a stern, formal 'immediately', as in commands like 「即刻中止せよ」. In everyday speech say 「すぐに」; in instructions and notices 「直ちに」; for on-the-spot reactions 「即座に」. Others add nuances: 「咄嗟に」 split-second reflexes, 「たちまち」 sudden change of state, 「早速」 getting started, 「すかさず」 seizing the moment. 「即時」 modifies nouns; 「時を移さず」 is written prose. Antonyms: 「後日」, 「後刻」.

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

1. すぐさま、即時そくじ、即座そくざ。