# mammalian

/məˈmeɪɫiən/ (US) · /mæmˈeɪliən/ (UK) · CEFR C1 · Adjective

Source: https://englishreference.com/word/mammalian
Updated: 2026-05-07

## Definition

relating to mammals, which are animals that feed their babies with milk from the mother's body.

For teachers: relating to or characteristic of the class Mammalia. Typically describes biological processes, physical traits, or species belonging to this group.

## Examples

- Whales are mammalian creatures that live in the ocean.
- The researchers studied mammalian brain development to better understand how human memory functions.
- The transition from reptilian to mammalian jaw structures represents one of the most well-documented transformations in the vertebrate fossil record, illustrating a shift in both feeding and hearing mechanisms.

## Usage notes

- Primarily used as an adjective in scientific and academic contexts; less common as a noun referring to a specific mammal.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.