What is the smallest meaningful unit of language called?

The smallest meaningful unit of language is referred to as a morpheme. A morpheme can be a word itself or a part of a word, such as a prefix or suffix, that carries intrinsic meaning. For example, in the word "unhappiness," "un-" is a morpheme that indicates negation, "happy" is a morpheme that conveys the core meaning, and "-ness" is a morpheme that turns the adjective into a noun. It illustrates how morphemes can function independently or as components of larger words while maintaining their meanings.

In contrast, a phoneme is the smallest unit of sound in a language, which does not necessarily convey meaning on its own. A syllable is a unit of pronunciation that typically includes a vowel sound and may or may not have consonants, but it is not the smallest unit of meaning. Morphemic structure refers to the way morphemes are arranged within words; it is a concept related to morphemes rather than a definition of what they are.