Japanese Words for "Love"

The Difference between "Ai" and "Koi"

Mother and daughter
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Both "ai (愛)" and "koi (恋)" can be roughly translated as "love" in English. However, they have a slightly different nuance in Japanese. To find out more, we will take a look at words containing "ai" or "koi". To learn how to say "I love you" in Japanese, check out my article, "Talking About Love."

Words containing "Ai (愛)"Words containing "Koi (恋)"
愛読書 aidokusho
one's favorite book
初恋 hatsukoi
first love
愛人 aijin
悲恋 hiren
sad love
愛情 aijou
love; affection
恋人 koibito
one's boyfriend/girlfriend
愛犬家 aikenka
a dog lover
恋文 koibumi
love letter
愛国心 aikokushin
恋敵 koigataki
a rival in love
愛車 aisha
one's cherished car
恋に落ちる koi ni ochiru
to fall in love with
愛用する aiyousuru
to use habitually
恋する koisuru
to be in love with
母性愛 boseiai
mother's love, maternal affection
恋愛 renai
博愛 hakuai
失恋 shitsuren
disappointed love

"Koi" is a love for the opposite sex, or a feeling of longing for a specific person. It can be described as "romantic love" or "passionate love." While "ai" has the same meaning as "koi," it also has a definition of a general feeling of love. "Koi" can be selfish, but "ai" is a real love. Here are some lines that explain them well:

Koi is always wanting. Ai is always giving.

"Renai (恋愛)" is written with the kanji characters of both "koi" and "ai." This word means, "romantic love." "Renai-kekkon (恋愛結婚)" is a "love marriage," which is the opposite of "miai-kekkon (見合い結婚, arranged marriage)." "Renai-shousetsu (恋愛小説)" is "a love story" or "a romance novel." The title of the movie, "As Good As It Gets" was translated as "Renai-shousetuska (恋愛小説家, A Romance Novel Writer)."

Here are some proverbs that include "koi."

Koi ni shishou nashi
Love needs no teaching.
Koi ni jouge no hedate nashi
Love makes all men equal.
Koi wa shian no hoka
Love is without reason.
Koi wa moumoku.
Love is blind.
Koi wa nesshi yasuku same yasui
Love becomes deep easily, but cools down soon.


"Soushi-souai (相思相愛)" is one of the yoji-jukugo (四字熟語). It means, "to be in love with one another."

The Japanese sometimes use the English word "love" as well, though it is pronounced as "rabu (ラブ)" (since there is no "L" or "V" sound in Japanese). "A love letter" is usually called "rabu retaa (ラブレター)." "Koibumi (恋文)" sounds a bit dated, and it is more of a literary word than a conversational word.

"Rabu shiin (ラブシーン)" is "a love scene". Young people say "rabu rabu (ラブラブ, love love)" when they are very much in love.

"Ai (愛)" can be used as a female name. Japan's new royal baby was named Princess Aiko, which is written with the kanji characters for "love (愛)" and "child (子)." Click here to read more about Princess Aiko. However, "koi (恋)" is rarely used as a name.

There are another words pronounced the same as "ai" and "koi". Since their meanings are distinctly different, I don't think there is any confusion between them when used in the proper context. With different kanji characters, "ai (藍)" means, "indigo blue," and "koi (鯉)" means, "carp." Carp streamers that are decorated on Children's Day (May 5th) are called "koi-nobori (鯉のぼり)."