prey on

prey (up)on someone or something

Fig. to take advantage of someone or something. (See also prey on something. Upon is formal and less commonly used than on.) The people of that island prey on tourists and do not give them good treatment. I really don't want to seem to prey upon your kindness.

See also: prey

prey on something

[for an animal] to feed on another animal as a matter of habit or preference. Owls prey on mice. Many birds prey on snakes.

See also: prey

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prey on somebody also prey upon somebody

1. to commit a crime against someone Police are looking for street criminals who prey on tourists. Gangs that prey upon small business owners in the city's Chinatown may be spreading to the suburbs.

2. to have an effect on someone Guilt preyed on him for years after the accident.

Usage notes: sometimes said about something that has an effect on people's emotions: The ads prey on our fear of being alone.

See also: prey

prey on something also prey upon something

to kill an animal in order to eat it Spiders prey on small flies and other insects. Seals often prey upon the same fish people are trying to catch.

Usage notes: said about animals that kill other animals for food

See also: prey