Blending

Blending is a process of word formation in which parts of lexemes that are not themselves morphemes are combined to form a new lexeme. Familiar examples of blends (sometimes also called portmanteau words) are words like brunch, a combination of breakfast and lunch, or smog, a combination of smoke and fog. While not one of the major ways of forming new words, blending is used quite a bit in English in advertizing, productnaming, and playful language. The Word Spy website lists these blends:

Indeed, the sheer number of words of this sort that can be found in the Word Spy archives suggests the vitality of this process. Note that while most of the time the parts that are fused together to form blends are not themselves morphemes, sometimes a whole base or affix will be used; for example, Word Spy also lists the word celeblog (‘a blog written by a celebrity’) which is made up of the chunk celeb from celebrity and the word blog; the latter part has become a free morpheme in English in the last few years.