2. rendered impure by addition of deleterious substances; as, had to boil the contaminated water. Syn. -- polluted. [ WordNet 1.5 ]
3.1 (Computers) damaged by inclusion of incorrect data or information not belonging; as, The file was contaminated by a buggy editor. Syn. -- corrupted. [ PJC ]
4. appearing unethical due to a questionable source or motives; -- of money or activities; as, The fund was contaminated by a large donation from a mobster. Syn. -- tainted. [ PJC ]