Definition

1. Noun:
   • (Mineralogy): A small, rounded lump of a mineral substance, typically harder than the surrounding rock or sediment in which it is found.
   • (Botany): A small, rounded, wart-like protuberance or swelling on a plant, often on a root or stem.
   • (Anatomy/Medicine): A small node, knot, or lump of distinct tissue, often abnormal.

Usage Examples

• Mineralogy:
  • The geologist discovered a nodule of flint embedded in the chalk.
  • Iron nodules are sometimes found on the ocean floor.
• Botany:
  • Legumes like peas and beans have root nodules that contain nitrogen-fixing bacteria.
  • The plant's stem was covered in small, hard nodules.
• Anatomy/Medicine:
  • The doctor felt a small, firm nodule during the examination of the thyroid gland.
  • A skin nodule can be a sign of various conditions.

Advanced Usage

• "Nodule" in Geology/Sedimentology: Refers specifically to concretions, which are compact, often spherical masses formed by the precipitation of mineral cement within sedimentary spaces.
  • Manganese nodules are of economic interest for deep-sea mining.
• "Nodule" in Pathology: Describes a small, solid, palpable lesion, distinct from a cyst or a papule.
  • Rheumatoid nodules are a common extra-articular manifestation of the disease.

Variants and Related Words

• Nodular (adjective): Having the form of or resembling a nodule or nodules.
  • The patient presented with a nodular rash.
• Nodulation (noun): The process of forming nodules, especially on the roots of legumes.
  • Nodulation is essential for the symbiotic relationship between legumes and rhizobia bacteria.

Synonyms

• Lump: A compact mass of a substance, especially one without a definite or regular shape.
• Knot: A hard or swollen spot in a part of the body or a lump in a plant stem.
• Tubercle: A small rounded projection or protuberance, especially on a bone or on the surface of an animal or plant.
• Concretion (specific to geology): A hard, solid mass formed by the local accumulation of matter, especially within a rock.

Related Phrases/Compounds

• Root nodule: A specialized structure on the roots of certain plants, notably legumes, that houses symbiotic bacteria.
• Thyroid nodule: A growth (lump) in the thyroid gland, which may be solid or fluid-filled.
• Rheumatoid nodule: A firm lump of non-tender tissue, often associated with rheumatoid arthritis, typically found under the skin.

Noun

1. (mineralogy) a small rounded lump of mineral substance (usually harder than the surrounding rock or sediment)
2. small rounded wartlike protuberance on a plant
3. a small node