tr.v. con·tam·i·nat·ed, con·tam·i·nat·ing, con·tam·i·nates
1. To make impure or unclean by contact or mixture.
2. To expose to or permeate with radioactivity.
3. Linguistics To influence the semantic properties or phonological form of (a word or phrase); blend with: The Middle English word femelle was contaminated by the word male, resulting in the modern form female.
One that contaminates; a contaminant.
[Middle English contaminaten, from Latin contāmināre, contāmināt-; see tag- in the Appendix of Indo-European roots.]
Synonyms: contaminate, befoul, foul, poison, pollute, taint
These verbs mean to make dirty or impure: Pesticides contaminated the lake. Mud befouled his shoes. Noxious fumes foul the air. Farm runoff poisoned the fish. Exhaust polluted the air. Improper storage tainted the food.
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:
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.