Humanities › English Leach and Leech Commonly Confused Words Share Flipboard Email Print Dorling Kindersley/Getty Images English English Grammar An Introduction to Punctuation Writing By Richard Nordquist English and Rhetoric Professor Ph.D., Rhetoric and English, University of Georgia M.A., Modern English and American Literature, University of Leicester B.A., English, State University of New York Dr. Richard Nordquist is professor emeritus of rhetoric and English at Georgia Southern University and the author of several university-level grammar and composition textbooks. our editorial process Richard Nordquist Updated February 25, 2019 The words leach and leech are homophones: they sound alike but have different meanings. Definitions 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. Examples Batteries are difficult to dispose of and contain harmful heavy-metal compounds that may leach into the soil."The river water was more corrosive than the Detroit system's and caused more lead to leach from its aging pipes. Lead can be toxic, and children are especially vulnerable."(Reuters, "Michigan Attorney General Sues France's Veolia in Flint Water Crisis." The New York Times, June 22, 2016)Similar to bloodletting, leeches were used to draw out the "bad blood" that medieval physicians believed caused many of their patients' ailments."The sun rose in a cloudless sky, the same as before. We passed a large island without grass or tree or bush. The sun was a leech that sucked the moisture from our flesh."(Scott O'Dell, The King's Fifth. Houghton Mifflin, 1966)"She called him a leech, said he's always sponging off the rest of us."(Swati Kaushal, A Girl Like Me. Penguin, 2008) Idiom Alerts The expression leach away (something) or leach (something) away means to gradually erode or wash away.- "Normally the excess salt would be leached away as rainwater percolates down through the soil. In dry climates, however, where there isn't enough rain or irrigation to drive the water down that far, salts can accumulate in the root zone."(Ann Larkin Hansen, The Organic Farming Manual. Storey, 2010)- "'Nathan? Are you awake?' The sweetness quickly leached away at the touch of Roiphe's nasal voice, leaving a sourness tinged with anxiety, which, Nathan understood, was his default reaction to Roiphe."(David Cronenberg, Consumed. Scribner, 2014) Practice: Leaches or Leeches? (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 (a) "It's not pollution that makes the water so black; tannic acid naturally leaches into the river from cypress and pine trees growing along the shoreline."(Bruce Hunt)(b) In modern medicine, leeches are used in reconstructive surgery to provide a vacuum effect that helps stimulate blood circulation.