Translation guide
A very close, trusted friend; a confidant. In Japanese, this concept is expressed through specific terms emphasizing deep emotional bonds, trust, and intimacy, often with nuances of lifelong connection or shared secrets.
To refer to a very close friend with whom one shares secrets and deep trust.
The most common and natural term for a very close friend, implying deep trust and a long-standing relationship. Suitable for both casual and formal contexts.
彼は私の親友です。
He is my bosom friend.
親友に秘密を打ち明けた。
I confided my secret to my bosom friend.
Literally 'friend of the heart', this phrase emphasizes a deep emotional and spiritual connection. It can sound slightly poetic or dramatic.
彼女は私の心の友だ。
She is my bosom friend.
Means 'one's only bosom friend' or 'best and only friend', emphasizing an irreplaceable bond. Used in more emphatic or literary contexts.
彼は私にとって無二の親友だ。
He is my one and only bosom friend.
To emphasize a friendship that has lasted since childhood or for a very long time.
Refers to a childhood friend, often implying a deep, enduring bond. Can be used for friends of the same or opposite sex.
彼女は私の幼なじみで、親友でもある。
She is my childhood friend and also my bosom friend.
A literary idiom meaning 'a friend from childhood' (literally 'bamboo horse friend'). It evokes a nostalgic, lifelong bond but is rarely used in daily conversation.
To highlight the aspect of sharing secrets or personal matters.
Means a trusted confidant or right-hand person. Often used in contexts of loyalty and deep trust, sometimes in professional or historical settings.
彼は社長の腹心の友として知られている。
He is known as the president's bosom friend and confidant.
Literally 'a dagger kept in one's bosom', this term refers to a trusted confidant or right-hand man, often in political or business contexts. It implies someone who acts on behalf of another with complete trust.
彼は総理の懐刀と呼ばれている。
He is called the prime minister's bosom friend and right-hand man.
While 友達 (ともだち) simply means 'friend', 親友 implies a much deeper, more intimate bond. Use 親友 only for your closest friends, not for casual acquaintances.
The English phrase 'bosom friend' can sound old-fashioned or literary. In Japanese, 親友 is the standard, natural equivalent. Avoid directly translating 'bosom' as 胸 (むね) unless you intend a poetic or metaphorical expression like 心の友.
彼とは竹馬の友だ。
He and I have been bosom friends since childhood.