- near-earth object.
- a combining form meaning “new,” “recent,” “revived,” “modified,” used in the formation of compound words: neo-Darwinism; Neolithic; neoorthodoxy; neophyte.
- a combining form used in the names of isomers having a carbon atom attached to four carbon atoms: neoarsphenamine.
- new, recent, or a new or modern form or development
- the most recent subdivision of a geological period
