遅延|ちえんchien[0]heiban (flat)

1. suru verb, intransitive verb, no-adjectivedelay; latency
   僕ぼくは電車でんしゃが遅延ちえんしたので遅刻ちこくした。↗

   I was late as a result of the train delay.

• Synonym遅れおくれNeutralNative word for being late or falling behind, used very broadly. 「遅延」 is the more formal choice, typical for train, delivery and payment delays.
• Synonym遅滞ちたいWrittenWritten word for things stalling or dragging; common in legal language, as in 「遅滞なく」. More formal than 「遅延」.
• Synonym延滞えんたいNeutralOverdue payment or an unmet deadline, as in 「延滞金」; used mainly for late payments and unreturned library books.
• Synonym滞りとどこおりNeutralStalling or falling behind in business or payments; often as 「滞りなく」, meaning things proceed smoothly without a hitch.
• Synonym遅らせるおくらせるNeutralVerb meaning to delay or slow something, as in 「出発を遅らせる」; more commonly used than 「遅らす」.
• SynonymディレイNeutralLoanword for delay, mostly in technical contexts and audio effects. In everyday speech 「遅れ」 is the natural choice.
• Related繰り延べるくりのべるWrittenVerb for pushing a schedule back deliberately. 「遅延」 describes the result of missing a scheduled time, not an active rescheduling.
• Related延期えんきNeutralActively postponing a set date to a later one. 「遅延」 instead means failing to make the scheduled time.
• Related猶予ゆうよWrittenGranting extra time or a grace period, as in 「執行猶予」; the emphasis is on allowing leeway rather than on the delay itself.
• Related持ち越すもちこすNeutralVerb for carrying an unfinished matter over to the next stage; the point is leaving it for later, not the lateness itself.
• Related繰り延べくりのべWrittenNoun for postponement, frequent in accounting, as in 「繰り延べ資産」. A written-style word for deliberate deferral.
• Related遅らすおくらすNeutralVerb meaning to delay or slow something down. 「遅延」 is a noun that focuses on the state of running late.
• Related延引えんいんWrittenWritten word for putting things off or being held up; rare even in formal prose. Everyday usage prefers 「遅延」 or 「延期」.
• Related遷延せんえんWrittenWritten word for something dragging on unresolved; rare, though medicine often uses it for lingering symptoms. Everyday speech says 「長引く」.
• RelatedもたもたCasualColloquial word for dawdling and moving slowly; it targets a person's sluggishness, not a scheduled event running late.
• Related延び延びのびのびCasualColloquial word for being put off again and again, as in 「工事が延び延びになる」. Repeated postponement, not a single delay.
• Antonym早着WrittenArriving ahead of the scheduled time, the opposite of a 「遅延」; used mainly for transport.

Use 「遅延」 when trains, deliveries or payments fail to arrive or happen on time; in casual speech 「遅れ」 works instead. For actively moving a date back, choose 「延期」; for overdue payments, 「延滞」. 「遅滞」 is legal prose, 「ディレイ」 technical, 「繰り延べる」/「繰り延べ」 deliberate deferral, 「猶予」 a grace period, 「持ち越す」 carrying matters over, 「もたもた」/「延び延び」 colloquial dawdling or repeated postponement, and 「早着」 the opposite: arriving early.

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

1. 予定よていの期日きじつや時間じかんに遅おくれること。間に合まにあわないこと。