Thesaurus:animal

• animal
• beast
• beastie (informal)
• creature    [⇒ thesaurus]
• critter (informal)
• deer (obsolete)

By sex or age

• female animal    [⇒ thesaurus]
• male animal    [⇒ thesaurus]
• youngling    [⇒ thesaurus]

Largest groups

• vertebrate    [⇒ thesaurus]
• invertebrate    [⇒ thesaurus]

Vertebrates

• fish    [⇒ thesaurus]
• amphibian    [⇒ thesaurus]
• reptile    [⇒ thesaurus]
• bird    [⇒ thesaurus]
• mammal    [⇒ thesaurus]

Invertebrates

• arthropod    [⇒ thesaurus]
• insect    [⇒ thesaurus]
• arachnid    [⇒ thesaurus]
• crustacean    [⇒ thesaurus]
• mollusc    [⇒ thesaurus]

By what they eat

• herbivore
• carnivore
• folivore
• frugivore
• insectivore
• omnivore

Informal kinds or categories

• bug
• creepy-crawly
• fowl    [⇒ thesaurus]
• livestock
• pet

• living thing
• organism    [⇒ thesaurus]