plat principal means 'main course' (of a meal) in French. There is no verb in that.
directeur or pricipal
un plat à emporter is a takeaway dish in French.
'un écran plat' is a flat screen in French.
A dish is 'un plat' in French.
the main course is called 'le plat principal', often shortened as 'le plat' in French.
plat (= dish)
plat(e)
le plat
Le plat principal.L'entréeLe plat (principal)Le fromageLe dessert
plat froid
plat préféré
Main dish