Definition

1. Noun:
   • A primitive mammal belonging to the infraclass Metatheria, characterized by giving birth to relatively undeveloped live young that typically complete their development in a maternal pouch. This group includes marsupials such as kangaroos, opossums, and koalas, which are found mainly in Australia and the Americas.

Usage Examples

• Noun:
  • The kangaroo is a well-known metatherian.
  • Unlike placental mammals, a metatherian has a distinctive reproductive strategy involving a pouch.
  • Fossil evidence suggests this extinct creature was a metatherian.

Advanced Usage

• In evolutionary biology, the term metatherian is used to distinguish these mammals from eutherians (placentals) and prototherians (monotremes).
  • The study compared the jaw structure of a eutherian fossil to that of a metatherian.

Variants and Related Words

• Metatheria (n): The scientific infraclass name to which metatherians belong.
  • Marsupials are classified under the infraclass Metatheria.

Synonyms

• Marsupial (Note: While all marsupials are metatherians, the term "metatherian" is broader and includes all members of the infraclass, including extinct relatives. In common usage, they are often synonymous.)

Different Meanings

• The term metatherian is specific to zoological and paleontological classification and does not have other general meanings.

Related Phrases/Idioms

• There are no common idioms or phrasal verbs using the word metatherian, as it is a specialized scientific term.

Noun

1. primitive pouched mammals found mainly in Australia and the Americas