growth ring

American  

noun

1. annual ring.

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growth ring British  

noun

1. another name for annual ring

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growth ring Scientific  

1. A layer of wood formed in a plant during a single period of growth. Growth rings are visible as concentric circles of varying width when a tree is cut crosswise. They represent layers of cells produced by vascular cambium.

2. ◆ Most growth rings reflect a full year's growth and are called annual rings. But abrupt changes in the environment, especially in the availability of water, can cause a plant to produce more than one growth ring in a year.

3. See more at dendrochronology

4. A similar layer in a part of an animal marking a period of growth, such as an annulus in a fish scale.

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Etymology

Origin of growth ring

First recorded in 1905–10

Example Sentences

By studying bone growth rings, spinal fusion, and developmental anatomy, researchers determined that the animal was roughly 20 years old when it died -- well into adulthood.

From Science Daily

By counting the sequence of rings, the researchers arrived at an estimated overall count of 100 to 120 growth rings, a spokesman said.

From BBC

They compare this century’s drought and other megadroughts using ancient records captured in the growth rings of trees.

From Los Angeles Times

For this they combined annual growth ring measurements on wooden building elements with the sudden spike of cosmogenic radiocarbon in 5259 BC.

From Science Daily

A common way to tell the age of a tree is by counting the growth rings in its trunk.

From NewsForKids.net