Definition of animal
(Entry 1 of 2)
1
: any of a kingdom (Animalia) of living things including many-celled organisms and often many of the single-celled ones (such as protozoans) that typically differ from plants in having cells without cellulose walls, in lacking chlorophyll and the capacity for photosynthesis, in requiring more complex food materials (such as proteins), in being organized to a greater degree of complexity, and in having the capacity for spontaneous movement and rapid motor responses to stimulation
2a
: one of the lower animals (see lower entry 3 sense 3) as distinguished from human beings
3
: a human being considered chiefly as physical or nonrational
also
: this nature
4
: a person with a particular interest or aptitude
a political animal He's a party animal.
5
: matter, thing
the theater … is an entirely different animal— Arthur Miller
also
: creature sense 1c
animal
adjectiveDefinition of animal (Entry 2 of 2)
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Merriam-Webster unabridged
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Time Traveler for animal
The first known use of animal was in the 14th century
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