growth ring
growth ring — noun
1. one of the circular bands that a tree trunk, bone, or shell forms in a single ye
one of the circular bands that a tree trunk, bone, or shell forms in a single year of growth; counting the bands shows how old the tree or animal is.
Daniel counted the growth rings on the old oak stump to guess its age.
collocation: count the growth rings to estimate age
Each summer adds a new growth ring just under the tree's bark.
The scientist studied the wide growth rings to learn about past rainy years.
Nila found clear growth rings inside the seashell she picked up on the beach.
Foresters use growth rings to tell how fast a forest has been growing.
- annual ring
the technical synonym; stresses that one ring forms each year
- tree ring
everyday term, used only for trees, not shells or bone
用法筆記
Usually plural — 'growth rings' — because the rings are read as a set to work out age; the singular names just one year's layer.