Refers to a physical or digital book for storing contact addresses. Common in both personal and business contexts.
I wrote my new friend's address in my address book.
スマホのアドレス帳を整理する。
I organize the address book on my smartphone.
I added my new friend to my address book.
I deleted people I no longer see from my address book.
I cleaned up my address book by deleting contacts I no longer use.
I synced my address book between my smartphone and computer.
Compound of アドレス (address) and 帳 (book, register). The word is a straightforward modern borrowing and combination.