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Related to preventer: Blowout preventer


v. pre·vent·ed, pre·vent·ing, pre·vents
1. To keep from happening; avert: took steps to prevent the strike.
2. To keep (a person or thing) from doing something; impede: prevented us from winning; prevented the disease from spreading.
3. Archaic
a. To anticipate or counter in advance.
b. To come before; precede.
To present an obstacle: There will be a picnic if nothing prevents.

[Middle English preventen, to anticipate, from Latin praevenīre, praevent- : prae-, pre- + venīre, to come; see gwā- in Indo-European roots.]

pre·vent′a·bil′i·ty, pre·vent′i·bil′i·ty n.
pre·vent′a·ble, pre·vent′i·ble adj.
pre·vent′er n.
Synonyms: prevent, preclude, avert, obviate, forestall
These verbs mean to stop or hinder something from happening, especially by advance planning or action. Prevent implies anticipatory counteraction: "Some contemporaries believed that capitalism and the rise of an international economy would prevent war among 'civilized' states" (John Howard Morrow).
To preclude is to exclude the possibility of an event or action: "a tranquillity which ... his wife's presence would have precluded" (John Henry Newman).
Avert and obviate imply that something, such as a difficulty or necessity, has been removed or avoided: The pilot's quick thinking averted an accident. The short duration of the journey obviated the need for large food supplies. Forestall usually suggests anticipatory measures taken to counteract, neutralize, or nullify the effects of something: We installed an alarm system to forestall break-ins.


1. a person or thing that prevents
2. (Nautical Terms) nautical a rope or other piece of gear rigged to prevent a sail from gybing
References in classic literature ?
During the most violent shocks of the Typhoon, the man at the Pequod's jaw-bone tiller had several times been reelingly hurled to the deck by its spasmodic motions, even though preventer tackles had been attached to it --for they were slack -- because some play to the tiller was indispensable.
It is also bad news for the UK's three million Asthma sufferers, who are urged to take their prescribed preventer medicine to reduce the risk of an attack due to increased pollen count.
Looking at the current market trends as well as the promising demand status of the "Blowout Preventer market", it can be projected that the future years will bring out positive outcomes.
Blow out preventer, blanketing and inerting are the applications, where the nitrogen generator SNG 4S plays a vital role
"There are two types of inhaler: A preventer and a reliever.
But Asthma UK is launching a campaign urging parents of children with asthma to make sure they take their usual preventer medicine and keep up a routine over the school break.
If a child hasn't kept up their preventer medicine routine over the holidays, they will be at greater risk of reacting to these triggers.
At these points of connection, a backflow preventer device must be installed.
Good management and control of your medication, such as using your preventer inhalGetting to grips with medication is key to relieving symptoms, says LloydsPharmacy Pharmacist Anshu Bhimbat.
with Good management and control of your medication, such as using your preventer inhaler daily, means there is no reason why you can't enjoy the sunshine.
"These findings support appropriate management of asthma with ICS preventer medications to ensure optimal asthma control," the authors write.