早々・早早|そうそうsousou[0]heiban (flat)

1. noun (suffix), noun, adverbas soon as ...; just after ...; immediately after ...
   私は角かどを曲まがって、開店かいてん早々そうそうの食堂しょくどうを見みつけた。↗

   I turned the corner and caught sight of a newly opened restaurant.
2. adverbhurriedly; in haste; quickly; promptly; earlyusu. as 早々に

• Synonym早速さっそくNeutralFor getting right down to something, as in 「早速始める」; it stresses starting at once, while 「早々」 is about just after something begins or acting early on.
• SynonymすぐNeutralThe most common everyday word for 'right away; soon', with the broadest range of use.
• SynonymすぐさまWrittenA written-style word for 'immediately', more urgent in tone than 「すぐ」.
• Synonym直ちにただちにWrittenFormal, for acting at once without any delay, as in 「直ちに避難」.
• SynonymすぐにNeutralCommon in speech; synonymous with 「すぐ」.
• Synonym即刻そっこくWrittenFormal, used chiefly in commands and orders, as in 「即刻退去」.
• Synonym即座にそくざにNeutral'On the spot, at once', as in 「即座に答える」; stresses acting without a moment's hesitation.
• SynonymさっさとNeutralCommon in speech for doing something briskly, without dawdling, as in 「さっさと帰る」.
• Synonymいち早くいちはやくNeutral'Before others; first', as in 「いち早く察知」; stresses getting ahead of everyone else.
• Synonym急遽きゅうきょWrittenA written-style word for acting hastily and suddenly, as in 「急遽中止」; stresses the impromptu, last-minute nature.
• SynonymたちまちNeutral'In an instant', stressing how quickly a change occurs, as in 「たちまち売り切れ」.
• Synonym至急しきゅうNeutral'Urgent; as fast as possible', often used to press someone to hurry with a task.
• Synonym早くはやくNeutralThe everyday word for 'early' or 'faster', as in 「早く来て」.
• RelatedさっとNeutralA mimetic word for a quick, sudden movement, as in 「さっと立ち上がる」.
• Related迅速じんそくWrittenA written-style noun for speed and swiftness, as in 「迅速な対応」.
• Related早いとこはやいとこCasualColloquial phrase for doing something promptly, with a hurry-up, prodding tone.
• RelatedとっととCasualBlunt and rough in tone, 'get a move on'; used mostly in commands.
• Related一も二もなくいちもにもなくNeutralAn idiom for doing something at once without hesitation, e.g. accepting a request or rushing off to help.
• Antonym遅々ちちWrittenAntonym: a written-style word for sluggish progress, as in 「遅々として進まない」.
• AntonymゆっくりNeutralAntonym: 'slowly; unhurriedly', the opposite of hurried 「早々」.

Use 「早々」 for something happening just after a point in time or early on, as in 「年明け早々」「早々に帰る」. To get right down to something, choose 「早速」; for everyday 'right away', 「すぐ」; formal 'immediately', 「直ちに」; urgent requests, 「至急」; getting ahead of others, 「いち早く」. For slow, unhurried action, use 「ゆっくり」.

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

1. そのようになってすぐの時期じき。「（体言たいげん）+早早（に）そうそう」「（動詞どうし連用形れんようけい）て+早早（に）そうそう」の形かたちで用もちいられることが多おおい。
2. はやばや。急いそいでやるさま。