What is an antonym for nucleolus?

There isn't a direct antonym for "nucleolus" in the way that you might find for words like "hot" and "cold."

Here's why:

* Nucleolus is a specific structure found within the nucleus of a cell. It's responsible for ribosomal RNA synthesis.

* Antonyms usually represent opposite concepts or features.

Instead of an antonym, consider these related concepts:

* Nucleoplasm: The fluid inside the nucleus that surrounds the nucleolus and chromosomes.

* Chromatin: The complex of DNA and proteins found in the nucleus.

* Cytoplasm: The fluid inside the cell that surrounds the nucleus.

If you're looking for a word to describe something that *lacks* a nucleolus, you might say:

* Anucleolate: This term refers to a cell or organism that does not have a nucleolus.

Ultimately, the best "opposite" depends on the context of your specific usage.