忘年会は会社の宴会の一つです。
The year-end party is one type of company banquet.
I was asked to give a speech at the wedding reception.
The company held its year-end party at a hotel.
I ended up attending a banquet with the business partner.
With the alcohol flowing, the party got really lively.
The new employee emceed the party.
宴会 highlights the festive, celebratory nature of a banquet with drinking, whereas 晩餐 focuses on the formal evening meal itself.
宴会 is a banquet or feast, typically larger, more festive, and often including drinking, while 会食 is a more neutral term for simply dining together.
宴会 is the standard modern word for a banquet, while 一座 is a literary or old-fashioned term for the same kind of gathering.