Person
al-Muṭṭalib ibn ʿAbd Manāf
المطلب بن عبد مناف
Lifespan unknown Banū al-Muṭṭalib
Brother of Hāshim and ʿAbd Shams. Founder of Banū al-Muṭṭalib. After Hāshim died in Gaza, al-Muṭṭalib travelled to Yathrib and brought back his nephew Shayba (= ʿAbd al-Muṭṭalib) — when people in Mecca saw him with the boy, they assumed Shayba was his slave and called him "ʿAbd al-Muṭṭalib" (the slave of al-Muṭṭalib), and the name stuck.
Significance
Brother of Hāshim and ʿAbd Shams. Founder of Banū al-Muṭṭalib. After Hāshim died in Gaza, al-Muṭṭalib travelled to Yathrib and brought back his nephew Shayba (= ʿAbd al-Muṭṭalib) — when people in Mecca saw him with the boy, they assumed Shayba was his slave and called him "ʿAbd al-Muṭṭalib" (the slave of al-Muṭṭalib), and the name stuck.
Sources: Wikipedia and classical Islamic biographical literature compiled by automated researchers. Every page is being continuously refined — if something looks off, please check back in a few days.