English Reference

Word

leech

US/ˈɫitʃ/

UK/lˈiːtʃ/

Countable noun

Definition

n. a small worm that lives in water and sucks blood from animals or people. In the past, doctors used them to treat sick people, but today the word is often used for someone who takes money or help from others without giving anything back.

n. a blood-sucking annelid worm typically found in freshwater environments. Historically used for bloodletting in medicine; in modern metaphorical usage, refers to a person who parasitically exploits others.

Examples

“The swimmer found a leech on his leg after leaving the pond.”

“He realized his cousin was a leech who only called when he needed to borrow money for rent.”

“While modern medicine has largely moved past bloodletting, surgeons occasionally use a medicinal leech to stimulate circulation in reattached tissue or skin grafts where blood flow is restricted.”

Examples

simple

“The swimmer found a leech on his leg after leaving the pond.”

contextual

“He realized his cousin was a leech who only called when he needed to borrow money for rent.”

complex

“While modern medicine has largely moved past bloodletting, surgeons occasionally use a medicinal leech to stimulate circulation in reattached tissue or skin grafts where blood flow is restricted.”

Usage

When used metaphorically for a person, it carries a strong negative connotation of exploitation.

Real-World Examples

“It tends to look like a parasite leeching off of the original building.”
CHRISTIAN GRECH 9 Feb 2026
“Gowan deduced that it was buried in landfills across south Wales – in a way that he thought allowed PCBs to leech into the surrounding water and soil.”
The Guardian 17 Aug 2026
“Even if scientists get lucky enough to leech a few fragments of megalodon DNA out of their teeth, this would only be the tiniest of baby steps in the right direction.”
Smithsonian Magazine 3 Aug 2018

Etymology

From Middle English leche (“blood-sucking worm”), from Old English lǣċe (“blood-sucking worm”), akin to Middle Dutch lāke ("blood-sucking worm"; > modern Dutch laak).

From Middle English leche (“physician”), from Old English lǣċe (“doctor, physician”), from Proto-West Germanic lākī, from Proto-Germanic lēkijaz (“doctor”), of disputed origin, but usually thought to be connected with Proto-Celtic (compare Old Irish líaig (“charmer, exorcist, physician”)); perhaps ultimately from Proto-Indo-European *leǵ- (“to collect, gather”). Cognate with Old Frisian lētza (“physician”), Old Saxon lāki (“physician”), Old High German lāhhi (“doctor, healer”), Danish læge (“doctor, surgeon”), Gothic 𐌻𐌴𐌺𐌴𐌹𐍃 (lēkeis, “physician”). Slavic words such as Serbo-Croatian ljèkār, Polish lekarz (“physician, doctor”) are usually considered to be borrowings from Germanic.

From Middle English lechen (“to cure, heal, treat”), from Middle English leche (“doctor, physician”). Compare Swedish läka (“to heal”).

From Middle English lek, leche, lyche, from Old Norse lík (“leechline”), from Proto-West Germanic līk, from Proto-Germanic līką (compare West Frisian lyk (“band”), Dutch lijk (“boltrope”), Middle High German geleich (“joint, limb”)), from Proto-Indo-European *leyǵ- ‘to bind’ (compare Latin ligō (“tie, bind”), Ukrainian нали́гати (nalýhaty, “to bridle, fetter”), Albanian lidh (“to bind”), Hittite link- (caus. linganu-) ‘to swear’ (with -n- infix).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

Domains

MedicineNautical

This entry

Exam level
CambridgeCambridgeCambridge English QualificationsThe exam suite from Cambridge University Press & Assessment, from A1 Movers up to C2 Proficiency. The benchmark names double as CEFR labels.C2 ProficiencyIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.8.5–9.0TOEFL iBTTOEFL iBTTest of English as a Foreign Language, Internet-Based TestETS's academic English test, the standard route for US university admissions. Scored 0–120, with a 1–6 scale since 2026.1–6 scale: 6.0114–120
Frequency
Occasional
Level
C2 · Proficiency
Updated

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English Reference