Word | Noun | Adjective | Verb | Adverb |
---|---|---|---|---|
Ordovician | Yes | No | No | No |
geological period | Yes | No | No | No |
Ordovician (noun) | geological period (noun) |
---|---|
the period from 500 million to 425 million years ago; characterized by conodonts and ostracods and algae and seaweeds | a unit of geological time during which a system of rocks formed |