1. A unit of weight equal to 2,000 pounds (0.907 metric ton or 907.18 kilograms). Also called net ton, short ton.
2. A unit of weight equal to 2,240 pounds (1.016 metric tons or 1,016.05 kilograms). Also called long ton.
3. A metric ton. See Table at measurement.
4. A unit of capacity for cargo in maritime shipping, normally estimated at 40 cubic feet.
5. A unit of internal capacity of a ship equal to 100 cubic feet.
6. A unit for measuring the displacement of ships, equal to 35 cubic feet, and supposed to equal the volume taken by a long ton of seawater.
7. often tons Informal
a. A large extent, amount, or number: has a ton of work; gets tons of fan mail.
b. Used adverbially with a or in the plural to mean "to a great degree or extent" or "frequently": felt a ton better; has seen her tons lately.
[Middle English tonne, a measure of weight; see TUN.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.