blow/let off steam, Informal. to give vent to one's repressed emotions, especially by talking or behaving in an unrestrained manner: Don't take her remarks too seriously—she was just blowing off steam.

Origin of steam

before 1000; Middle English steme, Old English stēam; cognate with Dutch stoom
Related formssteam·less, adjectiveout·steam, verb (used with object)pre·steam, adjective, verb (used with object)un·steamed, adjectiveun·steam·ing, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for blow off steam



the gas or vapour into which water is changed when boiled
the mist formed when such gas or vapour condenses in the atmosphere
any vaporous exhalation
informal power, energy, or speed
get up steam
  1. (of a ship, etc) to work up a sufficient head of steam in a boiler to drive an engine
  2. informalto go quickly
let off steam informal to release pent-up energy or emotions
under one's own steam without the assistance of others
Australian slang cheap wine
(modifier) driven, operated, heated, powered, etc, by steama steam radiator
(modifier) treated by steamsteam ironed; steam cleaning
(modifier) jocular old-fashioned; outmodedsteam radio


to emit or be emitted as steam
(intr) to generate steam, as a boiler, etc
(intr) to move or travel by steam power, as a ship, etc
(intr) informal to proceed quickly and sometimes forcefully
to cook or be cooked in steam
(tr) to treat with steam or apply steam to, as in cleaning, pressing clothes, etc
See also steam up

Word Origin for steam

Old English; related to Dutch stoom steam, perhaps to Old High German stioban to raise dust, Gothic stubjus dust
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for blow off steam



Old English steam "vapor, fume," from Proto-Germanic *staumaz (cf. Dutch stoom), of unknown origin. Steam age first attested 1941. Steam heat as a method of temperature control recorded from 1904.



Old English stemen, stymen "to emit a scent or odor," from the root of steam (n.). Slang meaning "to make angry" is from 1922. Related: Steamed; steaming.

Online Etymology Dictionary, © 2010 Douglas Harper

blow off steam in Science



Water in its gaseous state, especially at a temperature above the boiling point of water (above 100°C, or 212°F, at sea level). See Note at vapor.
A mist of condensed water vapor.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Idioms and Phrases with blow off steam

blow off steam

Also, let off steam. Air or relieve one's pent-up feelings by loud talk or vigorous activity. For example, Joan's shouting did not mean she was angry at you; she was just blowing off steam, or After spending the day on very exacting work, Tom blew off steam by going for a long run. This metaphoric term refers to easing the pressure in a steam engine. [Early 1800s]


see blow off steam; full speed (steam) ahead; get up steam; run out of steam; under one's own steam.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.