Diphyletic is a term used to refer to organisms that have evolved from two different ancestral species. Instead of using the word diphyletic, one can choose to use other words that would give the same meaning. Some other words that could be used in place of diphyletic are polyphyletic which refers to an organism that has evolved from multiple ancestral species. Another word that could be used is paraphyletic, which refers to an evolutionary grouping of organisms that excludes some of its descendants. These terms are important in taxonomy as they help to categorize organisms based on their evolutionary history.