nucleolus
Nucleolus (noun) means a small, rounded structure found inside the nucleus of a cell. Example: “Under the microscope, the nucleolus appeared as a dark, dense spot.”
How to use nucleolus
Learner’s notesIn plain EnglishA nucleolus is a small structure sitting inside a cell's nucleus.
This is a technical, scientific term mainly used in biology.
Fill the gap
Can you complete this real example?
Under the microscope, the _____ appeared as a dark, dense spot.
Etymology
The word combines nucleus with the Latin ending -olus, giving a term that essentially means a small nucleus-like body within the cell nucleus.