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Leach and Leech

Commonly Confused Words


The verb leach means to empty, drain, or remove.

The noun leech refers to a bloodsucking worm or to a person who preys on or clings to another. As a verb, leech means to bleed with leeches or to act as a parasite.


  • Batteries are difficult to dispose of and contain harmful heavy-metal compounds that may leach into the soil.

  • Similar to bloodletting, leeches were used to draw out the "bad blood" that medieval physicians believed caused many of their patients' ailments.

Answers to Practice Exercises:

(a) "It's not pollution that makes the water so black; tannic acid naturally _____ into the river from cypress and pine trees growing along the shoreline." (Bruce Hunt)

(b) In modern medicine, _____ are used in reconstructive surgery to provide a vacuum effect that helps stimulate blood circulation.

Answers to Practice Exercises

Glossary of Usage: Index of Commonly Confused Words

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