letalis

Letalis is a Latin adjective meaning deadly or lethal. It is formed from the noun letum, meaning death, with the adjectival suffix -alis. In classical and medieval Latin, letalis describes things that cause death or are capable of causing death, and in modern scientific Latin it appears in borrowed phrases and taxonomic epithets to convey lethality or fatality.

In English-language scholarship, letalis is typically encountered only as a Latin loanword or within Latin phrases, where it functions as an attributive descriptor. The most common English equivalents are lethal or fatal; letalis is used when a text aims to retain a Latin flavor or to signify a formally Latinized term. In taxonomy and biology, letalis may appear as a species epithet or part of a binomial name to indicate a deadly attribute, though it is not widely standardized and its use varies by author.

In other contexts, Letalis may be used as a proper name or title in fiction or branding, but such uses are creative rather than canonical. The word also appears in mottoes or historical documents that retain Latin phrasing.

See also: Lethal, Fatal, Letum, Latin terms in biology.