Latin Names and Terms for Family Members

English kinship terms, although not completely transparent even to those who grew up using them, lack the complexity found in many other language systems. English speakers might struggle to determine whether someone is a cousin once removed or a second cousin, but we don't have to think twice about what the title is for a parent's sister. It doesn't matter if the parent is the father or the mother: the name is the same: 'aunt'. In Latin, we would have to know whether the aunt is on the father's side, an amita, or on the mother's, a matertera.

This is not restricted to kinship terms. In terms of the sounds a language makes, there is a compromise made between ease of articulation and ease of understanding. In the realm of vocabulary, the ease might be the ease of memorizing a small number of specialized terms vs the need of others to know to whom you're referring. Sibling is more general than sister or brother. In English, we have both, but only those. In other languages, there might be a term for an older sister or younger brother and maybe none for a sibling, which could be considered too general to be useful. 

For those who grew up speaking, for instance, Farsi or Hindi, this list may seem as it should be, but for us English speakers, it may take some time.

• soror, sororis, f. sister
• frater, fratris, m. brother
• mater, matris, f. mother
• pater, patris, m. father
• avia, -ae, f. grandmother
• avus, -i, m. grandfather
• proavia, -ae, f. great-grandmother
• proavus, -i, m. great-grandfather
• abavia, f. great-great-grandmother
• abavus, m. great-great-grandfather
• atavia, f. great-great-great-grandmother
• atavus, m. great-great-great-grandfather
• noverca, -ae. f. stepmother
• vitricus, -, m. stepfather
• patruus, -i, m. paternal uncle
• patruus magnus, m. paternal great-uncle
• propatruus, m. paternal great-great uncle
• avunculus, -i, m. maternal uncle
• avunculus magnus, m. maternal great-uncle
• proavunculus, m. maternal great-great uncle
• amita, -ae, f. paternal aunt
• amita magna, f. paternal great aunt
• proamita, f. paternal great-great aunt
• matertera, -ae, f. maternal aunt
• matertera magna, f. maternal great-aunt
• promatertera, f. maternal great-great-aunt
• patruelis, -is, m./f. paternal cousin
• sobrinus, -i, m. maternal boy cousin
• sobrina, -ae, f. maternal girl cousin
• vitrici filius/filia, m./f. paternal step-sibling
• novercae filius/filia, m./f. maternal step-sibling
• filius, -i, m. son
• filia, -ae. f. daughter
• privignus, -i, m. stepson
• privigna, -ae, f. stepdaughter
• nepos, nepotis, m. grandson
• neptis, neptis, f. grand-daughter
• abnepos/abneptis, m./f. great-grandson/great-granddaughter
• adnepos/adneptis, m./f. great-great-grandso/great-great-granddaughter

Source

• Sandys, John Edwin, 1910. A Companion to Latin Studies. Cambridge University Press: London.