An Amalgamated name is a name that is form by combining several previously existing names. These may take the form of an acronym (where only one letter of each name is taken) or a blend (where a large part of each name is taken, such as the first syllable).
Reneesme Carlie Cullen Edward and Bella Cullen's child. Reneesme is the combining of Bella's mother's name "Renee" and Edward's adopted mother "Esme". Carlie is the combing of Bella's dad's name "Charlie" and Edward's adopted father's name "Carlisle". This takes place in Breaking Dawn, the final Twilight novel by Stephenie Meyer.
Linguistics
Amalagamation is also a term used in linguistics when a blend contains roots from several languages, without it being part of a blended language. For example, a word with an English and a Spanish root would not be an amalgam, but part of Spanglish, while a word with a Greek and a Latin root, would.