Translation guide
The English word 'double' covers many meanings, from 'twice as much' to 'two of something' to 'fold in half'. This guide organizes the most useful Japanese expressions by the intended meaning.
Expressing that an amount, number, or degree is two times the original.
Attaches to numbers or counters to mean 'times'. '2倍' means 'double' or 'twice'. Can also be used with verbs like 倍になる (to become double) or 倍にする (to make double).
This year's sales are double last year's.
給料が倍になった。
My salary doubled.
Explicitly 'two times', often interchangeable with 倍. Slightly more emphatic.
この部屋はあの部屋の二倍の広さだ。
This room is double the size of that one.
Formal or written term meaning 'to double' or 'increase twofold'. Often used in news or business contexts.
利益が倍増した。
Profits doubled.
Referring to something that has two parts, two layers, or two functions.
Means 'double' in the sense of two layers or two overlapping things. Common in words like 二重まぶた (double eyelid) or 二重構造 (double structure).
彼は二重まぶただ。
He has double eyelids.
この窓は二重ガラスです。
This window is double-glazed.
Loanword from English, used in many compound terms like ダブルベッド (double bed), ダブルス (doubles in tennis), or ダブルチェック (double-check).
Prefix meaning 'both' or 'double', used in words like 両手 (both hands), 両親 (both parents), 両方 (both sides). Not used alone.
両手で持ってください。
Please hold it with both hands.
To bend something so that one part covers another.
Transitive verb meaning 'to fold'. Often used with 半分に (in half).
紙を半分に折ってください。
Please fold the paper in half.
To fold up (e.g., a chair, map, clothes). Implies folding neatly for storage.
Literally 'to make into a two-fold', meaning to fold in half. More explicit than 折る.
書類を二つ折りにして封筒に入れた。
I folded the document in half and put it in the envelope.
Something that is exactly the same as another; a copy.
Noun meaning 'duplicate' or 'reproduction'. Often used for documents, keys, artworks.
鍵の複製を作りたいです。
I'd like to make a duplicate key.
Loanword for 'copy', very common for photocopies or digital copies.
A copy or transcript, often used in formal contexts like '写しを送付する' (send a copy).
A word or phrase that can be understood in two ways.
Literally 'double meaning'. Used to describe ambiguous statements.
その言葉には二重の意味がある。
That word has a double meaning.
A traditional Japanese rhetorical device using a pun or pivot word with two meanings. Not used in everyday speech.
和歌では掛詞がよく使われる。
In waka poetry, pivot words are often used.
In sports, a double can refer to a two-base hit in baseball, or doubles in tennis.
A double (two-base hit) in baseball.
彼はレフト線に二塁打を打った。
He hit a double down the left-field line.
Doubles (as opposed to singles) in tennis, badminton, etc.
To have a second function or use.
Means 'to serve also as' or 'to double as'. Attach to nouns.
このソファはベッドを兼ねています。
This sofa doubles as a bed.
Literally 'can also be used as'. A more roundabout way to express dual function.
この部屋は書斎としても使えます。
This room can double as a study.
English often uses 'double' as a verb (e.g., 'the number doubled'). In Japanese, use 倍になる (become double) or 倍増する (increase twofold) instead of trying to translate 'double' directly as a verb.
人口が倍になった。
The population doubled.
倍 (bai) alone can mean 'double' or 'times', but it's often used with a number. 二倍 (nibai) explicitly means 'two times'. In many contexts they are interchangeable, but 倍 is more common in casual speech when the number is clear from context.
I reserved a double bed.
ダブルチェックをお願いします。
Please double-check it.
その椅子は折りたためます。
That chair can be folded up.
Please make a copy of this document.
領収書の写しを同封します。
I enclose a copy of the receipt.
明日ダブルスの試合があります。
I have a doubles match tomorrow.