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:
What made you want to look up Mytilidae? Please tell us where you read or heard it (including the quote, if possible).
Can you spell these 15 tricky spelling words?
Take the quiz
Do you know these words that come from names?
Take the quiz
Test your knowledge - and maybe learn something along the way.
Take the quiz
Build a city of skyscrapers—one synonym at a time.
Play the game
