agglutinative

Agglutinative is a term in linguistic typology describing a class of languages in which words are formed by stringing together a sequence of morphemes, each of which typically expresses a single grammatical meaning. In agglutinative systems, affixes are joined to a base with clear boundaries between morphemes, making it relatively easy to identify the function of each part. Morphemes are usually attached in a linear chain and can be prefixes, suffixes, or infixes, with suffixation being the most common in many languages.

A defining feature is morphological transparency: meanings such as tense, aspect, mood, voice, number, case, or evidentiality are expressed by distinct, separate affixes. This often results in long but highly regular word forms, where the contribution of each affix is fairly predictable. However, languages may vary in how aggressively they employ affixation, and some mix agglutinative patterns with other types of morphology.

Representative languages commonly cited as agglutinative include Turkish, Finnish, Hungarian, Japanese, Korean, Quechua, and Basque. Turkish and Finnish, in particular, display extensive chains of suffixes with numerous case markers and agreed forms, while Japanese and Korean attach multiple grammatical suffixes to verb stems to encode tense, mood, politeness, and other categories.

Agglutinative morphology is often contrasted with fusional morphology, where a single affix can encode multiple grammatical meanings and boundaries are less distinct, and with isolating languages, which rely little on affixation. Many languages show mixed or intermediate features, and scholars sometimes describe them as partly agglutinative or moderately agglutinative.