YOU SAID:

I am, by definition, my own best friend.

INTO JAPANESE

私は、定義上、私自身の親友。

BACK INTO ENGLISH

I defined above, my own best friend.

INTO JAPANESE

私は私の自身の親友、上記定義。

BACK INTO ENGLISH

I was my own best friend, the above definition.

INTO JAPANESE

私は私の自身の親友、上記の定義です。

BACK INTO ENGLISH

I am defining my own best friend, above.

INTO JAPANESE

私自身の親友、定義上。

BACK INTO ENGLISH

My own best friend, by definition.

INTO JAPANESE

自分の親友、定義によって。

BACK INTO ENGLISH

His best friend, by definition.

INTO JAPANESE

彼の親友、定義によって。

BACK INTO ENGLISH

His best friend, by definition.