Epenthetically is an adverb that pertains to the addition of a letter or a sound to a word that's not a phonological part of a word's original pronunciation. It is sometimes called excrescence. Synonyms for the word epenthetically include phonetically, linguistically, etymologically, orthographically, and programmatically. Each of these words is related to the study or understanding of language and how words are constructed. Phonetically and linguistically can be used when talking about the sounds of language. Etymologically is used when discussing the history and origins of words. Orthographically is used to describe how words are spelled, and programmatically is a term used to describe how computer programs are designed to add characters.