Also found in: Thesaurus, Financial, Encyclopedia.
v. a·massed, a·mass·ing, a·mass·es
1. To gather together or accumulate a large quantity of (something): amass evidence; amass a fortune.
2. To be the site of (an increasing mass), especially as a result of neglect: How long has the desk been amassing bills?
To come together; collect: troops amassing on the border. See Synonyms at gather.
[Middle English, to accumulate, from Old French amasser, to assemble : a-, to (from Latin ad-; see ad-) + masser, to gather together (from Latin massa, lump, mass; see mass).]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.