the.com/coming out party

means A social or personal moment when someone publicly reveals an identity, fact, or new status they'd previously kept private — originally a debutante's formal introduction to society, now used for everything from LGBTQ+ coming out to a startup's launch.

from Rooted in the old debutante tradition of the late 1800s, where a young upper-class woman was formally 'brought out' into society at a ball — presented as ready for courtship and social life. 'Coming out' later took on a second life in gay culture by at least the mid-20th century, borrowing the same structure of a hidden thing stepping into the light, though here the party is often metaphorical and the gloves are definitely off.