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dam 1 (dăm)
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n.
1.
a. A barrier constructed across a waterway to control the flow or raise the level of water.
b. A body of water controlled by such a barrier.
2. A barrier against the passage of liquid or loose material, as a rubber sheet used in dentistry to isolate one or more teeth from the rest of the mouth.
tr.v. dammed, dam·ming, dams
1. To hold back or confine by means of a dam.
2. To close up; obstruct: He tried to dam his grief.
[Middle English.]
dammer n.
(click for a larger image)
dam1
Shasta Dam, on the Sacramento River, near Redding, California
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
dam 2 (dăm)
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n.
1. A female parent of an animal, especially a domesticated mammal such as a horse.
2. Archaic A mother.
[Middle English dam, dame, lady, mother; see DAME.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
dam 3
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abbr.
decameter
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
Dam (dăm, däm), (Carl Peter) Henrik 1895-1976.
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Danish biochemist. He shared a 1943 Nobel Prize for the discovery of vitamin K.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 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:

    Indo-European Roots

    Semitic Roots

    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.

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