nullius

Nullius is a Latin form meaning "of no one" or "none." It is the genitive singular of nullus, an adjective used to indicate absence or negation. The term appears in many Latin phrases and formulas, where it is used to express possession or attribution.

Terra nullius is the most well-known phrase containing nullius. Literally "land of no one," it denotes territory considered unclaimed or without recognized sovereignty under the law. Historically, terra nullius was used to justify acquiring territory during European colonial expansion. In Australia, the doctrine supported British sovereignty over the continent despite the presence of Indigenous peoples; the 1992 case Mabo v Queensland (No 2) rejected terra nullius as a legal basis for extinguishing native title and affirmed recognition of Indigenous land rights. The concept is widely criticized for masking Indigenous sovereignty and legal occupancy.

Nullius in verba is another commonly cited phrase using nullius, translating to "take no one's word for it" and serving as the motto of the Royal Society since its founding. It expresses an emphasis on evidence and inquiry rather than authority.

In other contexts, nullius appears in Latin inscriptions and legal phrases as a grammatical form rather than a standalone term. It remains primarily a linguistic element rather than a concept on its own in modern usage.

Etymology: from nullus, meaning "no" or "none"; the form nullius is the genitive singular. See also Terra nullius; Nullius in verba.