A language shift happens when words are increased or decreased. A child learning to talk will have a language shift as will a person experiencing a stroke, dementia, or other illness.

Language shift, sometimes referred to as language transfer or language replacement or assimilation, is the progressive process whereby a speech community of a language shifts to speaking another language.

language shift or language replacement.

Language loss is an overarching term which includes both language shift and language attrition.

A language replacement, usually known as a language shift, is in broad terms a cultural phenomenon where the predominant language spoken by one culture is changed to another language.

This can be the result of several key factors. One of the most dominant causes of a language shift is due to foreign colonization, where the colonizing nation imposes its culture and language on the colony, and the colony adopts them.

On the opposite hand, a language shift can also occur when communities of immigrants move to another location. A trend has shown where immigrants eventually drop their former language in favor of the predominant language spoken in the culture they now reside.