Definition

Noun: A type of worm characterized by a long, soft, cylindrical body that is divided into numerous ring-like segments, both in its internal anatomy and external appearance. This segmentation is a defining feature of the phylum Annelida.

Usage

The term "annelid worm" is used in biological and zoological contexts to describe and classify these segmented invertebrates. It is a formal, scientific term.

Examples

• Noun:
  • The biologist studied the movement of an annelid worm under the microscope.
  • Earthworms and leeches are common examples of annelid worms.
  • The sediment sample was rich in marine annelid worms.

Advanced Usage

• Used attributively to describe related concepts:
  • The annelid worm population serves as a key bio-indicator for soil health.

Variants and Related Words

• Annelid (noun/adjective): The more common short form; refers to any member of the phylum Annelida.
  • The phylum Annelida includes over 22,000 species.
• Polychaete (noun): A class of mostly marine annelid worms, often with bristled appendages.
• Oligochaete (noun): A class of annelid worms that includes earthworms, characterized by few bristles.
• Hirudinea (noun): The class of annelid worms comprising the leeches.

Synonyms

• Segmented worm: A descriptive synonym emphasizing the key anatomical feature.
• Bristle worm (specifically for polychaetes): A common name for many marine annelids.

Related Phrases/Compounds

• Annelid anatomy: Refers to the study of the body structure of these worms.
• Annelid phylogeny: The evolutionary history and relationships within the annelid group.

Notes

The term is a compound noun where "annelid" specifies the biological class and "worm" describes the general vermiform (worm-like) body shape. In precise scientific writing, "annelid" is often used alone.

Noun

1. worms with cylindrical bodies segmented both internally and externally