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 Xanthophyceae? Please tell us where you read or heard it (including the quote, if possible).
Think you’re an emoji 👓 expert? Let’s see 🤔
Take the quiz
Surprisingly specific words for shapes.
Take the quiz
Test your knowledge - and maybe learn something along the way.
Take the quiz
Listen to the words and spell through all three levels.
Play the game
