A portmanteau is a word created by combining parts of two or more other words. This often results in a word that captures the essence of both of the original words, sometimes with a humorous or satirical effect.
Here are some examples of portmanteaus:
* Smog: smoke + fog
* Brexit: British + exit
* Spork: spoon + fork
* Chunnel: Channel + tunnel
* Blog: web + log
So, while "blended words" isn't a commonly used term, it's likely that you are referring to portmanteaus.