To make avuncular in character; to transform into or treat with the qualities of an uncle's relationship.
From 'avuncular' plus the productive English suffix '-ize,' allowing the abstract quality to become an action verb meaning to imbue with uncle-like characteristics.
This word barely exists in published texts, but when anthropologists want to describe how a society formally treats certain male relatives, they use terms like this to capture the cultural remaking of a biological relationship!
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