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ADD
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abbr.
attention deficit disorder

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
add (ăd)
Share:
v. add·ed, add·ing, adds
v.tr.
1. To join or combine (numbers) through addition: If you add 5 and 10 and 17, the result is 32. If you add 6 to 8, you get 14.
2. To join or unite so as to increase in size, quantity, quality, or scope: added 12 inches to the deck; flowers that added beauty to the dinner table.
3. To say or write further.
v.intr.
1. To find a sum in arithmetic.
2.
a. To constitute an addition: an exploit that will add to her reputation.
b. To create or make an addition: gradually added to my meager savings.
Phrasal Verb:
add up
1. To be reasonable, plausible, or consistent; make sense: The witness's testimony simply did not add up.
2. To amount to an expected total: a bill that didn't add up.
3. To formulate an opinion of: added up the other competitors in one glance.
Idiom:
add up to
To constitute; amount to: The revisions added up to a lot of work.

[Middle English adden, from Latin addere : ad-, ad- + dare, to give; see dō- in the Appendix of Indo-European roots.]

adda·ble, addi·ble adj.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

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