Definition

Noun: 1. A small, dense, spherical structure within the nucleus of a cell: The nucleole (more commonly called the nucleolus) is a non-membrane-bound organelle composed of protein and RNA. Its primary function is the assembly of ribosomal RNA (rRNA) and the initial construction of ribosomes, which are essential for protein synthesis.

Usage Notes

• The term "nucleole" is a less common variant of the standard term "nucleolus". In modern scientific English, "nucleolus" is the predominant and preferred term.
• It is a countable noun (plural: nucleoles or nucleoli).
• It functions as a subject or object in a sentence, typically within the context of cell biology.

Examples

• As Subject:
  • The nucleole is often the most prominent structure visible within the nucleus under a light microscope.
  • During cell division, the nucleole temporarily disassembles.
• As Object:
  • The researcher stained the cell to highlight the nucleole.
  • Proteins required for ribosome assembly are concentrated in the nucleole.

Advanced Usage

• "Nucleolar" (adjective): Pertaining to or of the nature of a nucleole/nucleolus.
  • The study focused on nucleolar organization.
  • A nucleolar defect can impair ribosome production.

Variants and Related Words

• Nucleolus (n.): The standard and most widely used term for this organelle.
• Nucleolar (adj.): The adjective form.
• Ribosome (n.): The cellular particle whose components are manufactured in the nucleolus.
• rRNA (ribosomal RNA) (n.): The type of RNA synthesized and processed in the nucleolus.

Synonyms

• Nucleolus (This is the direct and primary synonym, not a different word).

Different Meanings

The word "nucleole" has only one specific meaning in modern English: the organelle within the cell nucleus. It is a specialized biological term with no common idiomatic or figurative uses.

Noun

1. a small round body of protein in a cell nucleus; such organelles contain RNA and are involved in protein synthesis