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si·lo (sīlō)
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n. pl. si·los
1.
a. A usually tall cylindrical structure, typically next to a barn, in which silage is produced and stored.
b. Any of several other structures or containers used for the same purpose, such as a covered trench or a polyethylene bag.
2. An underground shelter for a missile, usually equipped to launch the missile or to raise it into a launching position.
3. Each of the various departments, groups, or processes within a business or organization where work is done in isolation apart from the others.
tr.v. si·loed, si·lo·ing, si·los
1. To store in a silo.
2. To isolate (a department, group, or process) within a business or organization from others: “Taking a cue from the finance world, he divided the company's departments into 30 distinct units, meaning that the shoe department was siloed from, say, the menswear department” (Gaby Del Valle).
[Spanish, from Old Spanish, underground cavity, grain storage pit, silo, probably of pre-Roman substrate origin; akin to Basque zilo, zulo, hole, lair, den.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. 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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