leech

verb

leeched; leeching; leeches

intransitive verb

: to attach oneself to a person as a leech

… she would leech on to him and drain the life out of him.

—W. L. Gresham

transitive verb

1

: to bleed by the use of leeches

2

: to drain the substance of : exhaust

… bankers who had always leeched them white.

—D. A. Munro

Examples of leech in a Sentence

Recent Examples on the Web

Isolating rare earth minerals involves a huge amount of water and leeching with some of the world’s most toxic acids over hundreds of extraction stages. —Charlie Campbell, Time, 21 Apr. 2026

And typically, Wegmann added, those units are occupied by productive, working adults, not layabouts or career criminals leeching off the system, as the old narrative goes. —Matthew Adams, Fort Worth Star-Telegram, 9 Mar. 2026

First of all, most batteries contain cobalt, nickel, manganese, and other heavy metals that can be potentially toxic, and keeping them out of landfills ensures that these metals don’t leech out and pollute drinking water or the natural environment. —Katherine Gallagher, Treehugger, 20 Jan. 2026

Like a parasite, the goal seems to be to walk a fine line to leech off of business owners without completely killing the host. —Adam Summers, San Diego Union-Tribune, 20 Oct. 2025

Word History

Etymology

derivative of leech entry 1

First Known Use

1641, in the meaning defined at transitive sense 1

Phrases Containing leech

• medicinal leech

Rhymes for leech

• beach
• beech
• bleach
• breach
• breech
• each
• keech
• leach
• meech
• peach
• preach
• reach

Kids Definition

leech

noun

ˈlēch

1

: any of numerous flesh-eating or bloodsucking usually flattened worms that are made up of segments and have a sucker at each end

2

: a person who clings like a leech to another person for advantage or gain : parasite

Etymology

Old English lǣce "doctor, physician"

Word Origin

In the early days of medicine, a physician, known in Old English as a lǣce, often drew blood from patients. These doctors acted in the belief that good health depended on a balance of four controlling fluids in the body. These four fluids were called humors, and one of them was blood. In those days physicians believed that a person became ill if there was too much blood or too little of any of the other humors in the body. Thus they used a controlled bleeding of the patient, or bloodletting as it was called, to balance the humors. An easy way to do this was to attach bloodsucking worms to the body. These worms are common in all parts of the world and especially in marshes and swamps. Today we call these sucking worms leeches, taking the name from those ancient doctors who used them so often.

Medical Definition

leech

1 of 2 noun

ˈlēch 

: any of numerous carnivorous or bloodsucking annelid worms that comprise the subclass Hirudinea, that typically have a flattened segmented lance-shaped body with well-marked external annulations, a sucker at each end, a mouth within the anterior sucker, and a large stomach with pouches of large capacity at the sides, that are hermaphroditic usually with direct development, and that occur chiefly in freshwater although a few are marine and some tropical forms are terrestrial see medicinal leech

leech

2 of 2 transitive verb

1

: to treat as a physician : cure, heal

2

: to bleed by the use of leeches