English Reference

Word

thrash

US/ˈθɹæʃ/

UK/θɹˈæʃ/

Definitions

01to move wildly

B2 · Upper Intermediate

v. to move your arms and legs around in a violent or uncontrolled way.

v. to move about wildly or violently; to flail, often as a result of struggle or lack of control.

“The swimmer began to thrash his arms in the water when he felt a cramp.”

“The injured animal continued to thrash about in the undergrowth, making it difficult for the vet to administer a sedative safely.”

Synonyms

flailtosswrithe

02to defeat easily

B2 · Upper Intermediate Sports Informal

v. to beat an opponent or another team by a very large score.

v. to defeat an opponent utterly or decisively in a competition or contest.

“Our local team managed to thrash the champions four-nil in a surprise victory.”

“The incumbent candidate thrashed his rival in the primary election, securing a majority in nearly every district.”

Synonyms

trounceroutcrush

Antonyms

03to beat physically

C1 · Advanced Literary

v. to hit a person or animal many times as a punishment.

v. to beat mercilessly or repeatedly, typically with a stick or whip.

“In the old novel, the cruel master threatened to thrash the servant for being late.”

“The historical account describes how prisoners were thrashed for the slightest infractions of the camp's arbitrary rules.”

Synonyms

04computing memory issues

C2 · Proficiency Computing Technical

v. when a computer spends all its time moving data instead of doing work, making it very slow.

v. to undergo poor performance in a virtual memory system where excessive paging prevents productive processing.

“The server started to thrash because too many heavy applications were running at once.”

“System throughput plummeted as the machine began to thrash, with the hard drive light remaining solid due to constant page swaps.”

05music genre

B2 · Upper Intermediate Uncountable noun Music Informal

n. a fast and loud type of heavy metal music.

n. a subgenre of heavy metal music characterised by its fast tempo and overall aggression.

“He spent his teenage years listening to thrash and playing the drums.”

“The band's early work is considered a cornerstone of eighties thrash, blending punk speed with complex guitar structures.”

Synonyms

thrash metal

Usage

The verb is transitive when meaning to beat something, but often intransitive when describing wild movement, frequently followed by 'about' or 'around'.

Pitfall

he was thrashing his legs about the bed

he was thrashing his legs about on the bed

When describing wild movement in a location, 'thrash about' requires a preposition like 'on' or 'in' to connect to the place.

Real-World Examples

“They thrashed Hungary 6-0 and scored umpteen long-range screamers before losing 4-3 to Belgium in a thriller.”
The Guardian 12 Aug 2026
“A meeting between Miguel Ángel Gil Marín, the club’s chief suit, and Alvarez is scheduled, where the latter’s future will be thrashed out.”
The Guardian 18 Aug 2026

Etymology

From Middle English thrasshen, a dialectal variant of thresshen, threshen (whence the modern English thresh), from Old English þrescan, from Proto-Germanic *þreskaną, whence also Old High German dreskan, Old Norse þreskja.

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

Idioms

Domain

Computing

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.B2 FirstIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.5.5–6.5TOEFL 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: 4.0–4.572–94TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.785–944
Frequency
Occasional
Level
B2 · Upper Intermediate
Updated

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English Reference