What is the process called when bound morphemes are added to a word stem?

The process referred to when bound morphemes are added to a word stem is known as affixation. Affixation involves the addition of prefixes or suffixes, which are types of bound morphemes that cannot stand alone as words. This process modifies the meaning of the base word or alters its grammatical function, creating new words or forms. For example, adding the suffix "-ing" to the verb "play" forms "playing," demonstrating how affixation changes the word's tense.

Other options describe different linguistic processes. Blending refers to the combination of parts of two different words to create a new word, such as "brunch" from "breakfast" and "lunch." Dissimilation is a phonological process where similar sounds in a word become less similar, often for ease of pronunciation. Archaism refers to words or expressions that are no longer in common use and may appear outdated. These distinctions clarify how affixation specifically involves the attachment of morphemes to alter or expand words, emphasizing its unique role in linguistics.