Question

Define insertional inactivation (Give me the simplest defination plz.)

Answer 1

Insertional inactivation is the inactivation of a gene upon insertion of another gene inside in its place or within its coding sequence.
Hope it was helpful I provided you the simplest definition

Answer 2

a technique of recombinant DNA technology used to select bacteria that carry recombinant plasmids; a fragment of foreign DNA is inserted into a restriction site within a gene for antibiotic resistance, thus causing that gene to become nonfunctional.