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influenza

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noun in·flu·en·za \ˌin-(ˌ)flü-ˈen-zə\

Simple Definition of influenza

  • medical : a common illness that is caused by a virus and that causes fever, weakness, severe aches and pains, and breathing problems

Source: Merriam-Webster's Learner's Dictionary

Full Definition of influenza

  1. 1 a (1) :  an acute typically severe respiratory disease caused by an orthomyxovirus (species Influenza A virus of the genus Influenzavirus A) and marked by sudden onset, fever, prostration, severe aches and pains, and progressive inflammation of the respiratory mucous membranes —called also influenza A (2) :  either of two usually milder or even subclinical respiratory diseases caused by two other orthomyxoviruses (species Influenza B virus of the genus Influenzavirus B and species Influenza C virus of the genus Influenzavirus C) —often used with the letter B or C to denote the causative species b :  any of various human respiratory infections of undetermined cause —not used technically

  2. 2 :  any of numerous febrile usually virus diseases of domestic animals marked by respiratory symptoms, inflammation of mucous membranes, and often systemic involvement

influenzal

play \-zəl\ adjective

Origin and Etymology of influenza

Italian, literally, influence, from Medieval Latin influentia; from the belief that epidemics were due to the influence of the stars


First Known Use: 1743


INFLUENZA Defined for Kids

influenza

play
noun in·flu·en·za \ˌin-flü-ˈen-zə\

Definition of influenza for Students

  1. :  a very contagious virus disease like a severe cold with fever



History for influenza

The Italian word influenza was, like English influence, originally used in astrology. The effect that the stars and planets had on humans was attributed to the “inflow” (the literal meaning of influence) of an invisible liquid from the heavens. In the Middle Ages the Italian word was applied more narrowly to outbreaks of disease supposedly caused by unusual positions of the planets. In the 1600s and 1700s influenza came to refer specifically to the disease we now call by this name.


Medical Dictionary

influenza

play
noun in·flu·en·za \ˌin-(ˌ)flü-ˈen-zə\

Medical Definition of influenza

  1. 1a:  an acute, highly contagious, respiratory disease caused by any of three orthomyxoviruses: (1) or influenza A :  moderate to severe influenza that in humans is marked especially by sudden onset, fever, sore throat, fatigue, muscle aches, inflammation of the respiratory mucous membranes, and cough, is caused by any of several subtypes (such as H1N1, H2N2, or H3N2) of an orthomyxovirus (species Influenza A virus of the genus Influenzavirus A) infecting humans and various animals (such as birds or pigs), and may occur in seasonal epidemics or sometimes pandemics following mutation of the causative virus—see asian flu, avian influenza, bird flu, hong kong flu, spanish flu, swine flu, swine influenza (2) or influenza B :  influenza with less severe symptoms that is caused by an orthomyxovirus (species Influenza B virus of the genus Influenzavirus B) infecting only humans and especially children and that may occur in seasonal epidemics but not pandemics (3) or influenza C :  mild influenza that is often asymptomatic, is caused by an orthomyxovirus (species Influenza C virus of the genus Influenzavirus C) infecting only humans, and does not occur in epidemics or pandemicsb:  any human respiratory infection of undetermined cause—not used technically

  2. 2:  any of various viral diseases of domestic animals (as shipping fever of horses) marked especially by fever, respiratory symptoms, and inflammation of mucous membranes All types of influenza are commonly called “the flu.”

influenzal

\-zəl\play adjective <influenzal pneumonia> <influenzal symptoms>




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