添加|てんかtenka[0]heiban (flat)

1. noun, suru verb, transitive verbaddition; annexing

• Synonym付加ふかWrittenWritten/formal prose: attaching or adding something on as an extra, as in 「付加価値」; it stresses the incidental, attached nature rather than mixing in.
• Synonym追加ついかNeutralAdding something more afterwards, as in 「追加注文」; neutral and very common, it stresses the extra, later addition rather than mixing a substance in.
• Synonym補足ほそくNeutralSupplementing, filling in what is missing or insufficient, often extra explanation; 「添加」 instead puts a substance into something.
• SynonymプラスNeutralLoanword, casual: to add something on, as in 「牛乳にココアをプラスする」; also a plus sign or a benefit. More casual than 「添加」.
• Synonym補充ほじゅうNeutralReplenishing personnel or supplies to restore a full state; 「添加」 is adding a substance into something, not topping up a shortage.
• Synonym加えるくわえるNeutralThe all-purpose verb 'to add', covering far more than 「添加」: joining things in, increasing, including. Use it when no specific nuance is needed.
• Synonym足すたすNeutralColloquial verb: to add numbers or top something up, as in 「水を足す」; everyday speech, unlike the technical feel of 「添加」.
• Synonym付け足すつけたすNeutralColloquial verb: to add something on to what is already there, as in 「一言付け足す」; casual, versus the mixing-in sense of 「添加」.
• Synonym付け足しつけたしNeutralColloquial: the extra part added on afterwards. 「添加」 is about mixing a substance into something, while this just names what was tacked on.
• Synonym追録ついろくWrittenWritten/formal and rare: writing in an addendum afterwards; it concerns appended records, not adding substances.
• Synonym追補ついほWrittenWritten/formal and rare: a supplement added to a book to cover omissions; text-specific, unlike 「添加」.
• RelatedおまけNeutralColloquial: a freebie thrown in with a purchase, with a sense of something extra; 「添加」 means adding a substance into a product, not giving one away.
• Related補完ほかんNeutralFilling in what is lacking to make something complete; it stresses closing gaps, while 「添加」 simply mixes a substance in.
• Related添付てんぷNeutralAttaching documents or materials, as with email attachments or a photo sent with an application; 「添加」 is putting something into a thing.
• Related増補ぞうほWrittenWritten/formal: augmenting a published book with added content, as in 「増補改訂版」; specific to revising texts, not mixing substances.
• Related加増かぞうWrittenWritten/formal and rare: an increase, once used for adding to a stipend or domain; not used for food or chemical additives.
• Related補記ほきWrittenWritten/formal and rare: adding in writing what was left out, as an extra note or entry; narrower than 「添加」.
• Related足したしNeutralSomething that supplements or helps make up a shortfall, as in 「生活の足し」; about compensating, not mixing a substance in.
• Antonym除去じょきょWrittenWritten/formal: removing or getting rid of something — the direct opposite of adding a substance in with 「添加」.
• Antonym削除さくじょNeutralDeletion, mainly of text or data; the opposite of adding, used when striking things out rather than mixing them in.
• Antonym排除はいじょNeutralExclusion or removal, pushing something out or keeping it out from the start; the opposite of 「添加」.

Use 「添加」 for mixing a substance into food, medicine and the like, as in 「食品添加物」 and 「無添加」. For something added later say 「追加」, for something attached on 「付加」, for topping up 「補充」, and for attaching documents 「添付」. In everyday speech the verbs 「加える」 and 「足す」 cover general adding. Opposites: 「除去」 and 「削除」.

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

1. 付け加つけくわえること。付け加つけくわわること。
2. 薬剤やくざいや物質ぶっしつなどを混入こんにゅうすること。