Sufikso

A sufikso is a morpheme that attaches to the end of a word stem to alter its meaning or grammatical function. It is a type of affix, contrasted with prefixes that attach to the front and infixes that insert inside. Sufikso can be derivational, creating new words or changing word class, or inflectional, signaling tense, number, case, mood, and other grammatical categories. Sufikso are common across many language families, especially in agglutinative and fusional languages.

In Esperanto, sufikso is a central tool for word formation. The language uses a regular system of suffixes that attach to bases to indicate part of speech and grammatical role. The noun ending -o marks a noun, the adjective ending -a marks an adjective, and the adverb ending -e marks an adverb. The plural suffix -j can be added after the final vowel, yielding amikoj (friends). The accusative case is marked with -n, as in amikon (the friend as object). Abstract nouns are built with -eco, as in amikeco (friendliness) from amika (friendly). A productive derivational suffix is -ig-, which forms verbs from adjectives, as grandigi (to make large) from granda (large). Suffixes can be chained: amikeco demonstrates amik- + -ec- + -o.

In other languages, sufikso exist with similar roles: to mark tense, number, case, mood, or lexical category. Languages such as Turkish, Finnish, Russian, and English use suffixes extensively, often in long chains that convey multiple grammatical layers.