# monomer

/ˈmɑnəmɝ/ (US) · CEFR C1 · Noun

Source: https://englishreference.com/word/monomer
Updated: 2026-05-31

## Definition

a single, small molecule that can join with other similar molecules to form a much larger one. You can think of it as a building block for things like plastic or rubber.

For teachers: a molecule that can undergo chemical reactions to form chemical bonds with other molecules, resulting in the formation of a polymer. Often used in the context of synthetic materials and biological macromolecules.

## Examples

- The monomer is the basic unit of the plastic.
- In the lab, the students mixed the monomer with a catalyst to start the polymerization process.
- While the monomer itself is relatively inert, when subjected to high pressure and heat, it begins to link together in a long chain that forms the durable synthetic fiber used in textiles.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.