or fall-out



the settling to the ground of airborne particles ejected into the atmosphere from the earth by explosions, eruptions, forest fires, etc., especially such settling from nuclear explosions (radioactive fallout).Compare rainout.
the particles themselves.Compare rainout.
an unexpected or incidental effect, outcome, or product: the psychological fallout of being obese.
effects; results: emotional fallout from a divorce.

Nearby words

  1. fallopian tube,
  2. fallopian tubes,
  3. fallopio,
  4. fallot's tetralogy,
  5. fallot's triad,
  6. fallow,
  7. fallow deer,
  8. falls,
  9. fallujah,
  10. falmouth

Origin of fallout

First recorded in 1945–50; noun use of verb phrase fall out



verb (used without object), fell, fall·en, fall·ing.

to drop or descend under the force of gravity, as to a lower place through loss or lack of support.
to come or drop down suddenly to a lower position, especially to leave a standing or erect position suddenly, whether voluntarily or not: to fall on one's knees.
to become less or lower; become of a lower level, degree, amount, quality, value, number, etc.; decline: The temperature fell ten degrees. Stock prices fell to a new low for the year.
to subside or abate.
extend downward; hang down: Her hair falls to her shoulders.
to become lowered or directed downward, as the eyes: My eyes fell before his steady gaze.
to become lower in pitch or volume: Her voice fell, and she looked about in confusion.
to succumb to temptation or sin, especially to become unchaste or to lose one's innocence.
to lose status, dignity, position, character, etc.
to succumb to attack: The city fell to the enemy.
to be overthrown, as a government.
to drop down wounded or dead, especially to be slain: to fall in battle.
to pass into some physical, mental, or emotional condition: to fall asleep; to fall in love.
to envelop or come as if by dropping, as stillness or night.
to issue forth: Witty remarks fall easily from his lips.
to come by lot or chance: The chore fell to him.
to come by chance into a particular position: to fall among thieves.
to come to pass, occur, or become at a certain time: Christmas falls on a Monday this year. The rent falls due the first of every month.
to have its proper place: The accent falls on the last syllable.
to come by right: The inheritance fell to the only living relative.
to be naturally divisible (usually followed by into): The story fell into two distinct parts.
to lose animation; appear disappointed, as the face: His face fell when he heard the bad news.
to slope or extend in a downward direction: The field falls gently to the river.
to be directed, as light, sight, etc., on something: His eyes fell upon the note on the desk.
to collapse, as through weakness, damage, poor construction, or the like; topple or sink: The old tower fell under its own weight. The cake fell when he slammed the oven door.
(of an animal, especially a lamb) to be born: Two lambs fell yesterday.

verb (used with object), fell, fall·en, fall·ing.

to fell (a tree, animal, etc.).


an act or instance of falling or dropping from a higher to a lower place or position.
that which falls or drops: a heavy fall of rain.
the season of the year that comes after summer and before winter; autumn.
a becoming less; a lowering or decline; a sinking to a lower level: the fall of the Roman Empire.
the distance through which anything falls: It is a long fall to the ground from this height.
Usually falls. a cataract or waterfall.
downward slope or declivity: the gentle rise and fall of the meadow.
a falling from an erect position, as to the ground: to have a bad fall.
a hanging down: a fall of long hair.
a succumbing to temptation; lapse into sin.
the Fall, (sometimes lowercase) Theology. the lapse of human beings into a state of natural or innate sinfulness through the sin of Adam and Eve.
Slang. an arrest by the police.
surrender or capture, as of a city.
proper place: the fall of an accent on a syllable.
  1. an act or instance of holding or forcing an opponent's shoulders against the mat for a specified length of time.
  2. a match or division of a match.
a hairpiece consisting of long hair that is attached to one's own hair at the crown and usually allowed to hang freely down the back of the head so as to cover or blend with the natural hair.
an opaque veil hanging loose from the back of a hat.
a decorative cascade of lace, ruffles, or the like.
Machinery, Nautical. the part of the rope of a tackle to which the power is applied in hoisting.
Hunting. a deadfall.
the long soft hair that hangs over the forehead and eyes of certain terriers.
Armor. a pivoted peak projecting over the face opening of a burgonet.
Astrology. the sign of the zodiac in which the most negative influence of a planet is expressed (opposed to exaltationdef 5).
Mining. rock or ore that has collapsed from a roof, hanging wall, or the sides of a passage.

Verb Phrases

fall away,
  1. to withdraw support or allegiance: The candidate's supporters fell away when he advocated racial discrimination.
  2. to become lean or thin; diminish; decline.
  3. to forsake one's faith, cause, or principles: Many fell away because they were afraid of reprisals.
fall back, to give way; recede; retreat: The relentless shelling forced the enemy to fall back.
fall back on/upon,
  1. Also fall back to.to retreat to: They fell back on their entrenchments. The troops fell back to their original position.
  2. to have recourse to; rely on: They had no savings to fall back on.
fall behind,
  1. to lag, in pace or progress: We are falling behind in our work. Fatigued, some of the marchers fell behind.
  2. to fail to pay (a debt, obligation, etc.) at the appointed time: She fell behind in her tax payments, and the property was confiscated.
fall down, Informal. to perform disappointingly; to disappoint; fail: He was doing well on the exam until he fell down on the last essay question.
fall for, Slang.
  1. to be deceived by: Imagine falling for such an old trick.
  2. to fall in love with: He's not at all the type you would expect her to fall for.
fall in,
  1. to fall to pieces toward the interior; sink inward.
  2. to take one's place in the ranks, as a soldier.
  3. Also fall in with.to become acquainted with, especially by chance: We fell in with an interesting couple from Paris.
fall off,
  1. to separate from; withdraw.
  2. to decrease in number, amount, or intensity; diminish: Tourism falls off when the summer is over.
  3. Nautical.to deviate from the heading; fall to leeward.
  4. South Midland and Southern U.S.to lose weight, usually due to illness: She was sick all winter and fell off till she was just skin and bones.
fall on/upon,
  1. to assault; attack: The enemy fell on them suddenly from the rear.
  2. to be the obligation of: It has fallen on me to support the family.
  3. to experience; encounter: Once well-to-do, they had fallen on hard times.
  4. to chance upon; come upon: I fell upon the idea while looking through a magazine.
fall out,
  1. to quarrel; disagree: We fell out over who was to wash the dishes.
  2. to happen; occur: It fell out that we met by chance weeks later.
  3. to leave one's place in the ranks, as a soldier: They were ordered to fall out when the parade ended.
  4. Slang.to burst out laughing.
  5. South Midland and Southern U.S.to become unconscious; pass out.
fall through, to come to nothing; fail of realization: Despite all his efforts, the deal fell through.
fall to,
  1. to apply oneself; begin: to fall to work.
  2. to begin to eat: They fell to and soon finished off the entire turkey.
fall under,
  1. to be the concern or responsibility of.
  2. to be classified as; be included within: That case falls under the heading of errors of judgment.

Origin of fall

before 900; Middle English fallen, Old English feallan; cognate with German fallen, Old Norse falla; akin to Lithuanian pùlti to fall

Related formsun·fall·ing, adjective

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for fall out



the Fall theol Adam's sin of disobedience and the state of innate sinfulness ensuing from this for himself and all mankindSee also original sin


verb falls, falling, fell (fɛl) or fallen (ˈfɔːlən) (mainly intr)

to descend by the force of gravity from a higher to a lower place
to drop suddenly from an erect position
to collapse to the ground, esp in pieces
to become less or lower in number, quality, etcprices fell in the summer
to become lower in pitch
to extend downwardsher hair fell to her waist
to be badly wounded or killed
to slope in a downward direction
Christianity to yield to temptation or sin
to diminish in status, estimation, etc
to yield to attackthe city fell under the assault
to lose powerthe government fell after the riots
to pass into or take on a specified conditionto fall asleep; fall in love
to adopt a despondent expressionher face fell
to be avertedher gaze fell
to come by chance or presumptionsuspicion fell on the butler
to occur; take placenight fell; Easter falls early this year
(of payments) to be due
to be directed to a specific point
(foll by back, behind, etc) to move in a specified direction
to occur at a specified placethe accent falls on the last syllable
(foll by to) to return (to); be inherited (by)the estate falls to the eldest son
(often foll by into, under, etc) to be classified or includedthe subject falls into two main areas
to issue fortha curse fell from her lips
(of animals, esp lambs) to be born
British dialect to become pregnant
(tr) Australian and NZ dialect to fell (trees)
cricket (of a batsman's wicket) to be taken by the bowling sidethe sixth wicket fell for 96
archaic to begin to dofall a-doing; fall to doing
fall flat to fail to achieve a desired effect
fall foul of
  1. to come into conflict with
  2. nauticalto come into collision with
fall short
  1. to prove inadequate
  2. (often foll by of)to fail to reach or measure up to (a standard)


an act or instance of falling
something that fallsa fall of snow
mainly US autumn
the distance that something fallsa hundred-foot fall
a sudden drop from an upright position
(often plural)
  1. a waterfall or cataract
  2. (capital when part of a name)Niagara Falls
a downward slope or decline
a decrease in value, number, etc
a decline in status or importance
a moral lapse or failing
a capture or overthrowthe fall of the city
a long false hairpiece; switch
a piece of loosely hanging material, such as a veil on a hat
machinery nautical the end of a tackle to which power is applied to hoist it
nautical one of the lines of a davit for holding, lowering, or raising a boat
Also called: pinfall wrestling a scoring move, pinning both shoulders of one's opponent to the floor for a specified period
  1. another word for deadfall
  2. (as modifier)a fall trap
  1. the birth of an animal
  2. the animals produced at a single birth
take the fall slang, mainly US to be blamed, punished, or imprisoned

Word Origin for fall

Old English feallan; related to Old Norse falla, Old Saxon, Old High German fallan to fall; see fell ²



the descent of solid material in the atmosphere onto the earth, esp of radioactive material following a nuclear explosion
any solid particles that so descend
informal side-effects; secondary consequences

verb fall out (intr, adverb)

informal to quarrel or disagree
(intr) to happen or occur
military to leave a parade or disciplinary formation

sentence substitute

military the order to leave a parade or disciplinary formation
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 fall out
Online Etymology Dictionary, © 2010 Douglas Harper

Idioms and Phrases with fall out

fall out


Leave one's place in military ranks, as in After inspection they were ordered to fall out. [First half of 1800s]


Also, have a falling-out. Disagree, quarrel, as in The brothers fell out over their inheritance, or They no longer speak—they had a falling-out some years ago. [First half of 1500s]


Happen, result, as in Let us know how it falls out in the end. [Second half of 1500s]


In addition to the idioms beginning with fall

  • fall all over oneself
  • fall apart
  • fall asleep
  • fall away
  • fall back
  • fall back on
  • fall behind
  • fall between the cracks
  • fall by the wayside
  • fall down
  • fall flat
  • fall for
  • fall from grace
  • fall guy
  • fall in
  • falling down drunk
  • fall in line
  • fall in love
  • fall in place
  • fall into
  • fall in with
  • fall off
  • fall off the wagon
  • fall on
  • fall on deaf ears
  • fall on one's face
  • fall on one's feet
  • fall out
  • fall over
  • fall short of
  • fall through
  • fall through the cracks
  • fall to
  • fall under

also see:

  • bottom drops (falls) out
  • break one's fall
  • easy as pie (falling off a log)
  • let drop (fall)
  • let the chips fall where they may
  • ride for a fall
  • take the fall
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.