What is a common term for a person involved in the buying and selling of slaves?

The term that commonly refers to a person involved in the buying and selling of slaves is indeed "mango." In the context of historical commerce, especially in regions affected by the transatlantic slave trade, a "mango" denotes an intermediary or trader who dealt with the procurement and sale of enslaved individuals. This reflects a specific role within the larger framework of the slave trade, where such individuals facilitated transactions between sellers and buyers.

The other terms listed refer to different concepts. A "paedagogus" was typically a slave or servant responsible for the education and upbringing of children, particularly in wealthy households. "Familias" refers to a family or household, encompassing all members, free and enslaved, under the authority of the head of the household in Roman society. "Servus" simply translates to "slave" in Latin, denoting someone who is enslaved rather than a trader or dealer in slaves. Understanding these distinctions highlights the unique role of a "mango" in the historical context of slavery and trade.