The story
From barn + star. In the wiki sense a reference to the communal practice of barnraising, introduced on the MeatballWiki in the early 2000s and adopted by Wikipedia in 2003.
Etymology from Wiktionary, CC BY-SA 4.0.
barnstar
Today it means: A decorative painted object or image, often in the shape of a five-pointed star but occasionally in a circular wagon-wheel style, used to adorn a barn. Full definition →