Definition

1. Proper noun:
   • A specific geological time unit: The Jurassic Period is a major division of geological time within the Mesozoic Era, following the Triassic Period and preceding the Cretaceous Period. It is characterized by the dominance of dinosaurs, the first appearance of birds, and the proliferation of conifers and other gymnosperms.

Usage

• The term "Jurassic Period" is used as a proper noun to refer to this specific span of Earth's history. It is typically capitalized.
• It is used in scientific, educational, and popular contexts to discuss paleontology, geology, and evolutionary history.

Examples

• Proper noun:
  • The first birds evolved during the Jurassic Period.
  • Many famous dinosaurs, like Stegosaurus and Brachiosaurus, lived in the Jurassic Period.
  • The rocks from the Jurassic Period contain abundant fossils of marine reptiles.

Advanced Usage

• "The Jurassic": Often used as a shortened, informal form to refer to the Jurassic Period.
  • The climate during the Jurassic was generally warm and humid.

Variants and Related Words

• Jurassic (adjective): Of, relating to, or denoting the Jurassic Period.
  • Jurassic rocks are found on every continent.
• Mesozoic Era: The larger geological era containing the Triassic, Jurassic, and Cretaceous Periods.
• Age of Dinosaurs: A common descriptive name for the Mesozoic Era, which includes the Jurassic Period.

Synonyms

• The Jurassic: (Informal synonym)
• Jurassic System: (A term used in stratigraphy referring to the rock layers deposited during this period)

Related Phrases

• Jurassic/Cretaceous boundary: The transition point between the Jurassic and Cretaceous Periods.
• Late/Early/Middle Jurassic: Subdivisions (epochs) within the Jurassic Period used for more precise dating.

Noun

1. from 190 million to 135 million years ago; dinosaurs; conifers