immersion

noun
im·​mer·​sion | \ i-ˈmər-zhən How to pronounce immersion (audio) , -shən\

Definition of immersion

: the act of immersing or the state of being immersed: such as
a : baptism by complete submersion of the person in water
b : absorbing involvement immersion in politics
c : instruction based on extensive exposure to surroundings or conditions that are native or pertinent to the object of study especially : foreign language instruction in which only the language being taught is used learned French through immersion