What does biodegrade mean?
Biodegrade is an intransitive verb meaning to break down naturally into simple, harmless substances through the action of living organisms such as bacteria and fungi. When a material biodegrades, microorganisms consume it and convert it into compounds like water, carbon dioxide, and biomass, leaving no lasting pollution behind. The word rose to prominence alongside modern environmental awareness, becoming especially important in discussions of plastic pollution: conventional plastics may persist for centuries, while genuinely biodegradable alternatives can biodegrade within weeks or months under the right conditions. The term carries a broadly positive, eco-friendly connotation and appears constantly on packaging labels, though consumers should note that many items labelled biodegradable require industrial composting conditions to break down efficiently. Closely related forms include biodegradable (adjective), biodegradation (noun), and biodegradability. Because it combines the Greek root bios (life) with Latin degradare (to reduce in rank), the word literally captures the idea of life reducing a substance back to its natural state.
verbTo decompose naturally through the action of bacteria, fungi, or other living organisms, breaking down into harmless substances such as water, carbon dioxide, and organic matter.
- (of organic material) to decay naturally through the action of bacteria, fungi, or other living organisms, breaking down into simpler, environmentally benign substances
"The paper packaging will biodegrade completely within a few weeks in a compost heap."
"Unlike conventional plastics, these bags biodegrade within months when buried in soil."
"Environmental scientists measured how quickly the fishing line would biodegrade in seawater."
The word only entered English in the 1970s — humanity had to invent a word just to describe nature doing its job.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of biodegrade
Biodegrade is a twentieth-century coinage formed from the combining form bio-, from Greek bios meaning 'life', and degrade, which derives from Latin degradare, 'to reduce in rank or step down', itself built on gradus, 'step'. The word emerged in the early 1970s amid growing environmental concern about persistent synthetic waste, first appearing in technical literature before spreading into everyday usage. Its relatives include other bio- formations such as biology, biosphere, and biodegradable, all sharing the Greek root denoting life.
Related word forms
How biodegrade is actually used
A neutral-to-positive scientific and environmental term common in both technical contexts (waste management, ecology) and everyday consumer language. It is used almost exclusively with man-made or waste materials as the subject; we do not usually say leaves 'biodegrade' — they simply rot or decompose. The verb is often used with time expressions ('takes decades to biodegrade') to emphasize environmental persistence.
Easily confused with biodegrade
"Decompose" is the broader term for any breakdown of organic matter, while "biodegrade" specifically emphasizes decomposition carried out by living organisms and is typically used for man-made materials like plastics.
"Disintegrate" means to physically break into fragments or pieces, whereas "biodegrade" means to be chemically broken down by microorganisms into natural substances.