OsKar meets the mean that lives above him and they talk about how one word can describe life.
Mr. Black's roladex of "biographically significant" people.
The life in one word can also be a link to the Black Oskar meets that is in his building. The man when he met someone would wirte thier name down on a notecard and only one word to describe them or what they are known for in their life.
Mr. Black archives Oskar as well into his log of biographically significant people: "At first I was relieved, because I felt like everything I'd done had been worth it, because I'd made Dad into a Great Man who was biographically significant and would be remembered. But then I examined the card, and I saw it wasn't Dad."(286) This shows that Oskar made such an impact on Mr. Black by taking him out into the world again that Mr. Black has chosen to archive him as what he believes him most to be: a son.
The biography in one word isn't meant to sum up someone's life story, I think, but it is meant to describe what they perceive their purpose to be.
"Henry Kissinger: war!
Ornette Coleman: music!
Che Guevara: war!
Jeff Bezos: money!
Philip Guston: art!
Mahatma Gandi: war!
[...]
Arthur Ashe: tennis!
Tom Cruise: money!
Elie Wiesel: war!
Arnold Schwarzenegger: war!
Martha Stewart: money!
Rem Koolhaas: architecture!
Ariel Sharon: war!
Mick Jagger: money!
Yasir Arafat: war!" And so on and so forth!