When a child uses the word "cat" to refer to the family cat but not any other cats, occurs?

When a child uses the word "cat" to refer to the family cat but not any other cats, underextension" occurs.

Referring to a specific thing or item in a segregated sence yet neglecting to allude to another thing in a similar classification in that sence is a delineation of underextension. Usually utilized by youthful kids, for instance when a kid calls their teddy bear Teddy yet alludes to other teddy bears as 'toy'.

Urban growth invariably feeds increased commercialization and industrialization. it requires continually expanding land areas. when urbanization rates are high, and countries do not have the institutional and managerial capacities or economic wherewithal to manage such rapid growths, they exert intense pressure on the types and nature of the resulting settlements. they contribute to the development of overcrowded slums and shanty towns without adequate essential services and necessary infrastructure.-by asit k. biswas and cecilia tortajada