"Minyan" (מיניין) in Yiddish refers to the minimum number of Jewish adults (10 men or 10 men and 1 woman) required for a public prayer service, specifically for the recitation of the Amidah prayer.
It's possible you heard "minyan" pronounced with a slight accent or misheard it as "minyon".
If you're unsure about the context, please provide more information.