influenza

noun in·flu·en·za \ˌin-(ˌ)flü-ˈen-zə\

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

Full Definition of INFLUENZA

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

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

— in·flu·en·zal \-zəl\ adjective

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Origin 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

noun in·flu·en·za \ˌin-flü-ˈen-zə\

Definition of INFLUENZA for Kids

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

Word History of 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

noun in·flu·en·za \ˌin-(ˌ)flü-ˈen-zə\

Medical Definition of INFLUENZA

a : any of several acute highly contagious respiratory diseases caused by strains of three major orthomyxoviruses now considered to comprise three species assigned to three separate genera: (1) : influenza a (2) : influenza b (3) : influenza c b : any human respiratory infection of undetermined cause—not used technically

: any of numerous febrile usually virus diseases of domestic animals (as shipping fever of horses) marked by respiratory symptoms, inflammation of mucous membranes, and often systemic involvement

—in·flu·en·zal \-zəl\ adjective