Merriam-Webster Logo
SINCE 1828
Menu
dictionary thesaurus

promammal

noun
pro·​mammal | \ (ˈ)prō+\

Definition of promammal

1 : an extinct reptile exhibiting definite mammalian characteristics especially : a synapsid reptile
2a : a primitive mammal (as a platypus) not exhibiting all the characteristics of the group
b : one of the Protomammalia

Love words?

You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Start your free trial today and get unlimited access to America's largest dictionary, with:

  • More than 250,000 words that aren't in our free dictionary
  • Expanded definitions, etymologies, and usage notes
  • Advanced search features
  • Ad free!

History and Etymology for promammal

pro- entry 1 + mammal

Keep scrolling for more

Learn More about promammal

Statistics for promammal

Look-up Popularity

Comments on promammal

What made you want to look up promammal? Please tell us where you read or heard it (including the quote, if possible).

Show Comments  Hide Comments 

WORD OF THE DAY

intoxicate

Listen to the pronounciation of intoxicate

to affect and impair by alcohol or a drug

Get Word of the Day daily email!

Test Your Vocabulary

Words from Greek and Latin Quiz

  • roman forum
  • Which of the following months comes from a Latin word for “ten”?
Spell It

Can you spell these 10 commonly misspelled words?

TAKE THE QUIZ
Syn City

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Words at Play
Ask the Editors
Word Games