- A sedimentary material consisting of very fine particles intermediate in size between sand and clay. (noun)
- To become filled with silt: an old channel that silted up. (verb-intransitive)
- To fill, cover, or obstruct with silt: River sediments gradually silted the harbor. (verb-transitive)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.