prefikset

Prefikset is a term used in linguistic morphology and computer science to refer to the collection of prefixes that attach to a base form, or to all prefixes of strings in a given language. In morphology, a prefix is a bound morpheme placed at the beginning of a word to modify meaning or part of speech. The prefikset of a stem consists of all prefixes that yield recognizable, productive words in a language. Some prefixes are highly productive (for example, in English un-, re-, pre-), while others are limited to specific lexemes. The study of prefikset helps describe regularities in word formation and the constraints governing prefixation, including phonological adjustment, semantic shift, and syntactic compatibility.

In computer science, prefikset often means the set of prefixes of a string or of a language. For a word w, the prefikset includes all strings formed by taking the initial segments of w, typically including the empty string. Prefix sets underpin data structures such as tries (prefix trees) used for fast lookup, autocomplete, and spell checking. They also appear in the analysis of prefix codes, where the prefix property ensures unique decodability; Kraft’s inequality relates the lengths of codewords in a prefix code to possible code alphabets and code lengths.

The term prefikset is used in Norwegian and other Germanic languages as a direct translation of 'prefix set.' In scholarly writing, it may appear in discussions of morphology, formal languages, or information retrieval, always with context that distinguishes between the linguistic prefix set and the computational prefix set.