debutante [débbyoo taant]
(plural debutantes)
n
young woman introduced into society: a young woman who is being introduced formally into society by appearing at a formal social event such as a dance or party for the first time
[Early 19th century. < French , 'leading off' < present participle of débuter (see debut)]
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So what the hell do you call someone making his/her debut?
I naturally assumed it was a debutant.