ScienceAugust 9, 2026

formalin

FOR-muh-lin

Definition

A dilute solution of formaldehyde in water, commonly used as a chemical preservative or disinfectant.

Etymology

The word is a proprietary name derived from 'formic acid' and the chemical suffix '-in,' first coined in the late 19th century for the commercial distribution of formaldehyde solutions.

In the news

In the context of studying sewage pathogens, formalin is used to preserve samples for microscopic analysis, ensuring that the structural integrity of parasites like Cyclospora is maintained.

I study pathogens in sewage. Here’s how cyclospora could be getting into our food.

Read the full article ↗

The Washington Post

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