from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A layer in a large body of water, such as a lake, that sharply separates regions differing in temperature, so that the temperature gradient across the layer is abrupt.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A layer within a body of water or air where the temperature changes rapidly with depth.
from The Century Dictionary and Cyclopedia
- n. A layer within a large body of water sharply separating portions of it which differ in temperature, so that the temperature-gradient through the layer is very abrupt.
thermo- + -cline (Wiktionary)