等価|とうかtouka[1]atamadaka (head-high)

1. no-adjectiveequivalence; equal value; parity
   １ドルは現在げんざい１１０円えんと等価とうかである。↗

   One dollar is equivalent to 110 yen.
2. noun(logical) equivalence

• Synonym同等どうとうNeutralSame degree or rank, as in 「大卒と同等」; 等価 focuses on equal value.
• SynonymイコールNeutralColloquial loanword meaning 'equals', as in 「AイコールB」; not restricted to value.
• Synonym等しいひとしいNeutralAn adjective for being equal in quantity, value or degree, as in 「二辺が等しい」; 等価 is a noun centered on value.
• Synonym同値どうちWrittenWritten/formal; in logic it means two propositions are equivalent, while 等価 can also mean equal value.
• Synonym等値とうちWrittenEqual value or numerically equal; also interchangeable with 「同値」. Rarely used; close to 等価, which is the everyday choice.
• Related平等びょうどうNeutralEquality without discrimination, typically of rights or treatment; never about value.
• Related同じおなじNeutralThe most general word for 'same'; it does not emphasize equal value.
• Related同様どうようNeutralMeans 'just like' or similar, as in 「同様の手口」; stresses resemblance rather than equal value.
• Related同一どういつWrittenWritten/formal word for being exactly the same, one and the same; stresses identity.
• Related同質どうしつWrittenWritten/formal word for having the same quality or nature, as in 「同質化」.
• Related同格どうかくWrittenWritten/formal word for the same status or rank; also the grammatical term 'apposition'.
• Related等量とうりょうWrittenWritten/formal word for equal quantity or amount, as in 「等量の水」.
• Antonym不等価WrittenWritten/formal antonym meaning unequal value; used rarely.

For equal value or price, use 「等価」, as in 「等価交換」. For 'same' in general, say 「同じ」; for the same degree or rank, use 「同等」; to describe equality, use the adjective 「等しい」; for logical equivalence, use 「同値」.

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

1. 価値かちや値段ねだんが等ひとしいこと。
2. 二ふたつの命題めいだいの一方いっぽうが真しんであれば他方たほうも真しん、一方いっぽうが偽にせであれば他方たほうも偽にせであること。