/ˈanəməl/
Noun, pl. animals
1. A living organism belonging to Kingdom Animalia that possess several characteristics that set them apart from other living things, such as:
a. being eukaryotic (i.e. the cell contains a membrane-bound nucleus) and usually multicellular (unlike bacteria and most protists, an animal is composed of several cells performing specific functions) ;
b. being heterotrophic (unlike plants and algae that are autotrophic, an animal depends on another organism for sustenance) and generally digesting food in an internal chamber (such as a digestive tract);
c. lacking cell wall (unlike plants, algae and some fungi that possess cell walls);
d. being generally motile, that is being able to move voluntarily;
e. embryos passing through a blastula stage;
f. possessing specialized sensory organs for recognizing and responding to stimuli in the environment.
(biology-online.org)
2. A living organism that feeds on organic matter, typically having specialized sense organs and nervous system and able to respond rapidly to stimuli. (dictionary.com)
Adjective
1. Of or relating to animals (biology-online.com)
Word origin: Middle English, from Latin, from animāle, neuter of animālis, living, from anima, soul.