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a. Susceptible to physical harm or damage: trees that are vulnerable to insects;
b. Susceptible to emotional injury, especially in being easily hurt: a lonely child who is vulnerable to teasing.
c. Susceptible to attack: "We are vulnerable both by water and land, without either fleet or army" (Alexander Hamilton).
d. Open to censure or criticism; assailable: The mayor is vulnerable to criticism on the issue.
2. Games In a position to receive greater penalties or bonuses in a hand of bridge. In a rubber, used of the pair of players who score 100 points toward game.

[Late Latin vulnerābilis, wounding, from Latin vulnerāre, to wound, from vulnus, vulner-, wound; see welə- in Indo-European roots.]

vul′ner·a·bil′i·ty, vul′ner·a·ble·ness n.
vul′ner·a·bly adv.


1. The susceptibility of a nation or military force to any action by any means through which its war potential or combat effectiveness may be reduced or its will to fight diminished.
2. The characteristics of a system that cause it to suffer a definite degradation (incapability to perform the designated mission) as a result of having been subjected to a certain level of effects in an unnatural (manmade) hostile environment.
3. In information operations, a weakness in information system security design, procedures, implementation, or internal controls that could be exploited to gain unauthorized access to information or an information system. See also information; information operations; information system.




Achilles heel Any particularly vulnerable area; a weakness; a soft spot. This expression comes to us from Homer’s Iliad, a Greek epic poem depicting the events of the Trojan war. Achilles was its hero. Legend has it that at his birth Achilles’ mother, Thetis, immersed him in the river Styx in order to make him invulnerable. In doing so, she held him by one heel, which was therefore never touched by the water. Later, as a great warrior in the Trojan war, Achilles went unharmed by his enemies until Paris, whom Apollo had told the secret of Achilles’ heel, mortally wounded him by shooting an arrow into his heel. The first recorded use of the term was in 1810 in Coleridge’s The Friend:

Ireland, that vulnerable heel of the British Achilles!

The sinew connecting the back of the heel to the calf of the leg is called the Achilles tendon.

between two fires Under attack from both sides at once; caught in a precarious or dangerous situation with no way out. A soldier who was exposed to gunfire from two or more sides was said to be “between two fires.” This literal usage appeared as early as 1885.

He was about to find himself placed between two fires—viz. the Mahdi and the reinforced garrison of Metammeh. (Times, February 20, 1885)

On the figurative level current today, fire refers to any danger which threatens from all sides simultaneously.

between wind and water In a vulnerable, precarious position; exposed or unprotected, defenseless. Literally, the phrase refers to that part of the ship’s side which is alternately exposed and submerged, marking the fluctuation of the water line. Such an area is particularly vulnerable to attack and corrosion. Figuratively, the phrase refers to any vulnerable state or dangerous situation. The literal use appears as early as 1588, the figurative as early as 1652.

Now they have crackt me betwixt wind and water a’most past cure. Stay, let me feel my self. (Arthur Wilson, Inconstant Ladie, 1652)

Both levels of meaning remain in use today.

caught bending Taken by surprise; at a disadvantage; in a vulnerable position. A child bending over is not on his guard and is particularly well-positioned for a kicking or spanking. A 1903 song by George Robey included the line:

My word! I catch you bending!

caught flat-footed Caught unprepared, unready, by surprise, not “on one’s toes.” This phrase probably derives from baseball or football, and dates from the early 1920s. It refers to someone’s being caught (thrown out or tackled) while standing still or flat-footed. A person in such a position reacts less quickly than one “on his toes.”

caught with one’s pants down Taken completely off guard or entirely by surprise; found in a compromising or embarrassing position; hence, also unquestionably guilty; caught in the act, in flagrante delicto. General acceptance of this inelegant expression has been attributed to its appearance in a 1946 issue of The Saturday Evening Post

chink in one’s armor A weakness or vulnerability; an area in which one’s defenses are inadequate or ineffective; a personality flaw. The phrase alludes to the armor worn by knights. A chink ‘crack, cleft, or narrow opening’ could cost a knight his life. Figuratively, a chink in one’s armor refers to a personal rather than physical vulnerability. Some modern psychologists have adopted the word armor to mean ‘character or personality,’ emphasizing those aspects of one’s character which are formed in defense and serve self-protective functions.

clay pigeon A person or thing in a vulnerable position; an easy mark; one who can be easily taken advantage of; an easy job or task, a cinch. This American slang expression is an extension of the term clay pigeon as used in trapshooting, where it represents a disklike object of baked clay thrown into the air as a target. It has been in literal usage since 1888.

fair game A legitimate object of attack or ridicule; an easy target of derision. The term originated with wildlife laws limiting the hunting of certain animals to a specific time or season of the year, during which the hunted animals are “fair game.” In its figurative sense, this phrase refers to a person or thing whose manner or appearance makes him a likely victim of mockery.

In that character it becomes fair game for ridicule. (Jeremy Bentham, Chrestomathia, 1816)

gone coon One who is in bad straits; a person who is on the brink of disaster, whose goose is cooked; a lost soul, a “goner.” A “coon” (raccoon) who cannot escape from a hunter is a “gone coon.” A ludicrous fable probably fabricated to explain this expression tells of a raccoon which, trapped in a tree at gunpoint by Davey Crockett, said to the great marksman, “I know I’m a gone coon.” The Democratic party was aware of the fable when they applied the label coon to the Whigs during the presidential contest of 1840.

live in a glass house To be in a vulnerable position, to be open to attack; to live a public life, to be in the public eye. The expression plays on two well-known properties of glass—its transparency and its brittleness. The phrase is apparently a truncated version of the old proverb people who live in glass houses shouldn’t throw stones, dating from the early 17th century.

In the glass house world of commercial publishing, … Peter Mayer is something of a superstar. (Saturday Review, February, 1979)

on the ropes On the verge of ruin or collapse; at the mercy of whatever forces threaten to overcome one. The metaphor is from the boxing ring. When a prize fighter is on the ropes, he is in a weakened and very vulnerable position. His opponent is in control, and will probably soon be able to “finish him off.”

open season A time when persons or ideas in disfavor are subject to attack from all sides. The expression, of American origin, comes from hunting and refers to those periods during which various types of game are legitimate quarry.

out on a limb In a vulnerable, compromising, or risky position; at a disadvantage. This expression refers to the predicament of a person in a tree who, having climbed out onto one of the branches (limbs), faces the prospect of injury if the limb should not be strong enough to support him. The figurative implications are that a person has espoused an unconventional idea or cause which, if it fails, may precipitate his downfall, resulting in a loss of influence, prestige, and credibility.

No one is willing to go out on any limb. No one is willing to say yes or no to a proposition. He must always go to someone higher. (John Steinbeck, Russian Journal, 1948)

over a barrel In an embarrassing or uncomfortable position or situation; with one’s back against the wall, helpless, in someone else’s power. This chiefly U.S. slang expression dates from at least 1939. According to the OED the allusion is to the helpless condition of a person who, after having been saved from drowning, is placed over a barrel in order to clear the water out of his lungs.

sitting duck An easy mark or target, a ripe victim; a person or thing in an open or vulnerable position. The allusion is to the comparative ease of shooting a duck resting on the water as opposed to one in flight.

stick one’s neck out To expose one-self to danger or criticism; to take a chance, to risk failure; to invite trouble. This early 20th-century American expression plays with the idea that sticking one’s neck out is equivalent to asking to have one’s head chopped off. Thus vulnerability, usually nonphysical, is also implicit in the figurative uses of this expression.

We’ve stuck our necks out—we’re looking for trouble, see? (H. Hastings, Seagulls Over Sorrento, 1950)

turn turtle To be utterly helpless or defenseless. When turned on their backs, turtles are completely powerless and without defense. Turn turtle also means ‘to overturn, upset, capsize.’

up a tree Cornered, trapped, caught; at another’s mercy, in another’s power. The expression is said to come from coon hunting; once a raccoon is treed by the hounds, he’s a gone coon.

I had her in my power—up a tree, as the Americans say. (William Makepiece Thackeray, Major Gahagan, 1839)

where the shoe pinches The sore spot or vulnerable area; the true source of trouble or distress. This expression purportedly derived from Plutarch’s biography of Paulus Aemilius. Questioned as to why he divorced his fair, faithful, and fertile wife, Aemilius removed his shoe and replied, “Is it not handsome? Is it not new? Yet none knows where it pinches, save he that wears it.” This expression, equivalents of which exist in most European languages, appeared in English literature as early as the time of Chaucer.

Subtle enemies, that know … where the shoe pincheth us most. (Gabriel Harvey, Letterbook, 1580)

ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.vulnerability - the state of being vulnerable or exposed; "his vulnerability to litigation"; "his exposure to ridicule"
danger - the condition of being susceptible to harm or injury; "you are in no danger"; "there was widespread danger of disease"
2.vulnerability - susceptibility to injury or attack
weakness - the property of lacking physical or mental strength; liability to failure under pressure or stress or strain; "his weakness increased as he became older"; "the weakness of the span was overlooked until it collapsed"
defencelessness, defenselessness, unprotectedness - the property of being helpless in the face of attack
assailability - vulnerability to forceful attack
destructibility - vulnerability to destruction
breakability, fragility, frangibility, frangibleness - quality of being easily damaged or destroyed
exposure - vulnerability to the elements; to the action of heat or cold or wind or rain; "exposure to the weather" or "they died from exposure";
invulnerability - the property of being invulnerable; the property of being incapable of being hurt (physically or emotionally)


The condition of being laid open to something undesirable or injurious:
قابِلِيَّة الإنْجِراح
særanleiki; varnarleysi; viîkvæmni
kwetsbaarheidzwakke plek


[ˌvʌlnərəˈbɪlɪtɪ] Nvulnerabilidad f


[ˌvʌlnərəˈbɪləti] nvulnérabilité f


nVerwundbarkeit f; (= susceptibility)Verletzlichkeit f; (fig) → Verletzbarkeit f; (of police, troops, fortress)Ungeschütztheit f; the vulnerability of the young fish to predatorsdie Wehrlosigkeit der jungen Fische gegen Raubtiere; such is their vulnerability only 2% survivesie sind so wehrlos, dass nur 2% überleben; his emotional vulnerabilityseine Empfindsamkeit or Verletzbarkeit


[ˌvʌlnrəˈbɪlɪtɪ] nvulnerabilità


(ˈvalnərəbl) adjective
unprotected against attack; liable to be hurt or damaged. Small animals are often vulnerable to attack.
ˌvulneraˈbility noun


n. vulnerabilidad.
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