Semifreddo is an Italian dessert that literally means "half cold". This frozen dessert is typically made with heavy cream, egg yolks, and sugar, and is often flavored with chocolate, fruit, or nuts. If you're looking for synonyms for "semifreddo", you could consider using "frozen mousse", "chilled custard", "frozen souffle", or "frozen parfait". These terms all describe a similar type of dessert that is chilled but not frozen solid like traditional ice cream. Another term that could be used interchangeably with "semifreddo" is "frozen dessert terrine", which is a fancy French term for a layered frozen dessert with the same texture as a semifreddo.