A hapax legomenon (or ) (pl. hapax legomena, though sometimes called hapaxes for short) is a word which occurs only once in the written record of a language, in the works of an author, or in a single text. They often prove important for attributing authorship of a work; for example, each of Shakespeare's plays contains a similar percentage of hapax legomena not found elsewhere in his work, something that would be difficult for a forger to duplicate. They also create difficulties in translation and decipherment, since inferring meaning from context becomes less certain with fewer examples. For example, many of the remaining undeciphered Mayan glyphs are hapax legomena, and Biblical hapax legomena play a large role in disputes over Bible translation.
Note that the term refers to a word's appearance in a body of text, not to its origins, nor to its prevalence in speech. It thus differs from a nonce word, which may never be recorded, or may find currency and be recorded widely, or may appear several times in the work which coins it, and so on. If a word is used twice it is a dis legomenon, thrice, a tris legomenon. Beyond tetrakis legomenon (four times), there is no term for such a word.
Hapax legomenon is from the Greek ἅπαξ λεγόμενον "[something] said only once."
The term hapax legomenon is popular among Bible scholars, who take the number of hapaxes in a putative author's corpus as an indication of his vocabulary and thereby argue for or against attribution. The identification of a word as a hapax by these authors means that it occurs once in the Bible or, more specifically, once in the New Testament.
Some examples of hapax legomena in a given language or body of work are: