Definition

1. Noun:
   • A cephalopod mollusk of the Indian and Pacific Oceans: The "chambered nautilus" is a marine animal belonging to the cephalopod class, known for its distinctive external shell.
   • Characterized by a spiral shell with pearly partitions: Its shell grows in a logarithmic spiral and is divided into a series of connected, chambered compartments. The animal inhabits the outermost chamber.

Usage Examples

• Noun:
  • The chambered nautilus is often called a "living fossil" due to its ancient lineage.
  • We observed the beautiful, patterned shell of a chambered nautilus in the aquarium.
  • The chambered nautilus uses jet propulsion to move through the water.

Advanced Usage

• Scientific and poetic reference: The "chambered nautilus" is frequently cited in literature and science as a symbol of natural perfection, growth, and architectural beauty due to the mathematical precision of its shell.
  • The poet Oliver Wendell Holmes Sr. wrote a famous poem titled "The Chambered Nautilus."

Variants and Related Words

• Nautilus: Often used as a shorter, common name for the "chambered nautilus" ( and related species).
• Pearly nautilus: Another common name emphasizing the iridescent, pearly appearance of the shell's interior partitions.

Synonyms

• Nautilus: The most direct synonym.
• Cephalopod with a shell: A descriptive synonym highlighting its biological class and key feature.

Related Phrases and Terms

• "Living fossil": A common descriptive phrase applied to the chambered nautilus, noting that its form has remained relatively unchanged for millions of years.

Noun

1. cephalopod of the Indian and Pacific oceans having a spiral shell with pale pearly partitions