Brand extension
Using an established brand name to launch a product in a new category, so the newcomer borrows awareness and trust it would otherwise have to build from zero. It works when the parent brand's associations make sense in the new category and the product is good enough to keep them; it fails when they don't travel (Colgate Kitchen Entrees) or when the extension blurs what the parent brand stands for.
Where it's used
Used when a company with a strong brand wants to enter a new category without paying to build a new name. Good when the brand's main association still makes sense in the new category and the product can live up to it.
Example
From one beauty bar to a whole bathroom shelf
DoveDove launched in the US in 1957 as a beauty bar with moisturising cream. It carried the same promise of mild, caring skin care into body wash, deodorant, hair care and, in 2010, Dove Men+Care. Each step made sense because the parent association still applied in the new category. Compare Colgate Kitchen Entrees, frozen meals from a toothpaste brand, which did not last.