- 1[uncountable, countable] insertion (in/into something) the act of putting something inside something else; a thing that is put inside something else the insertion of a feeding tube Acupuncture involves the insertion of needles into specific points of the body.
- 2[countable, uncountable] a thing that is added to a book, piece of writing, etc.; the act of adding something the insertion of an extra paragraph
Check pronunciation: insertion