What is the term for a new word made by combining parts of existing words?
New words formed by fusing together parts of existing words are known as blends. They used to be called portmanteau words, but this term isn't used as much nowadays. Blends are very common in English and account for a very large number of the new words entering the language each year. Well-established blends include brunch, guesstimate, motel, fanzine, and shopaholic; among the more recent coinages are affluenza, infotainment, botnet, and labradoodle.
Blends are not strictly the same as compounds, which are made by joining whole words together, rather than parts of words. Examples include website, awayday, housemate, schoolboy, and landbanking.
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