(Latin: maternal uncle, uncle; mother's brother)

avuncular (uh VUNG kyuh luhr) (s) (adjective), more avuncular, most avuncular
1. Relating to a maternal uncle or mother's brother.
2. Regarded as characteristic of an uncle, especially in benevolence or tolerance; like an uncle in kindness or indulgence.
3. In medical genetics, pertaining to an aunt or uncle.
4. Etymology: from the Latin avunculus, "maternal uncle". The feminine equivalent of avuncular is materteral, "like an aunt".

An avuncular relationship is the genetic relationship between aunts and uncles and their nieces and nephews.

Dwight David Eisenhower, as U.S. President (1953 to 1961), was the amiable uncle, but his reputation as an indifferent manager evaporated once scholars got a look at his papers, which showed a much more engaged and sophisticated player than the avuncular image he cultivated.

—Compiled from "Does Temperament Matter?" by Nancy Gibbs in
TIME, October 27, 2008, pages 38-39.

"He himself [Josemaría Escrivá] was a polarizing figure, humble and grandiose, avuncular and ferocious."

—As seen in "The ways of Opus Dei", Time; April 24, 2006; pages 37-38.
avuncularity (s) (noun), avuncularities (pl)
1. The quality of being like an uncle or mother's brother.
2. Suggestive of an uncle especially in kindliness or geniality: "Grace's brother showed avuncular indulgence whenever he was with his nieces and nephews."
avunculate (s) (noun), avunculates (pl)
1. In some patrilineal societies, to have a special relationship similar to that of father and son that exists between a man and his sister's sons or his nephews.
2. The relationship between a man and his sister's children, generally her sons. With some tribal people, avunculate refers to a special relationship between a man and his maternal uncle, and the mutual responsibilities between them.
3. Etymology: from Latin avunculus, "uncle".
avunculism (s) (noun), avunculisms )pl)
A custom in some societies where the mother's brothers are very important in the family heritages or in children's upbringing.
avunculocal residence (s) (noun), avunculocal residences (pl)
A living pattern in which newly married couples stay with the family of the husband's maternal uncle.

Found in matrilineal societies where a nephew inherits property from his mother's brother.