Meaning

• To make something dangerous or toxic by introducing impurities or foreign matter.

  "This water is contaminated. It isn't safe to drink."

• To soil, stain, corrupt, or infect by contact or association.

• To make unfit for use by the introduction of unwholesome or undesirable elements.

  "Do not contaminate the peanut butter with the jelly."

• To infect, often with bad objects