"Formal" refers to something that follows established rules, customs, or practices. It typically involves behaving in a serious and proper manner, wearing appropriate attire, and using polite language. Full definition
The research looked at the experience of children in the first year of formal of education - who in nursery school and in reception had been used to more opportunities to play. (news.bbc.co.uk)
70 % of what employees learn in formal training programs is forgotten one day after the training is completed. (elearningindustry.com)
The stunning Dining Room has a tray ceiling with chandelier for formal dining. (ourvalleyhomes.com)