hapax

Hapax, short for hapax legomenon, is a term used in linguistics and textual criticism to describe a word or form that occurs only once within a defined corpus or text. The concept can apply to a single document, an author’s complete works, or an entire language’s published corpus.

Etymology traces the word to Greek, with hapax meaning “once” and legomenon meaning “that is said” or “said once.” The phrase has long been used in classical scholarship and later adopted by modern linguists and corpus analysts to flag lexical items with solitary appearances.

In practice, hapax refers to a specific occurrence within a corpus. The plural hapax legomena denotes multiple such items. There is also a distinction between hapax tokens (the single occurrences) and hapax types (the unique word forms themselves). In many contexts, hapax is used as a shorthand for hapax legomenon.

Hapaxes have limited statistical weight for frequency analyses because their rarity provides little information about general usage. They can indicate genuine lexical novelty, scribal or textual peculiarities, or gaps in a corpus or dictionary. In historical or literary studies, the presence of hapaxes can aid in authorship attribution, dating, or stylistic analysis, but they can also reflect transmission errors or transcriptional variants.

Examples commonly arise in biblical or classical texts, where a number of words occur only once in a given edition or language stage. Hapax analysis remains a standard tool in lexicography and corpus linguistics.