SINCE 1828

An Encyclopædia Britannica Company

Medical Dictionary

hydrarthrosis

play

noun hy·drar·thro·sis \ ˌhi-(ˌ)drär-ˈthrō-səs \

medical Definition of hydrarthrosis

plural hydrarthroses play \-ˌsēz\

:a watery effusion into a joint cavity

Seen and Heard

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

show

WORD OF THE DAY

glabrous

play

smooth or hairless

Words at Play

alt-59c17b8172892

'So Long': A Common But Mysterious Goodbye

Its origins are surprisingly murky.

alt-59c13729150dc

"Immune to" or "Immune from"?

Nobody is immune to this question.

alt-59bff395cf879

What's Going On With 'Nonplussed'?

Its recent usage is hard to shrug off.

alt-59bad350d88f1

Welcome to the New Words

From 'hive mind' to 'sriracha'

Ask the Editors

video-title-words-of-the-year-1066

Words of the Year: 1066

Or, Why Pig Meat is Called 'Pork' and Cow Meat is Called 'Beef'

How Often Is 'Biweekly'?

Don't get us started on 'bimonthly'

video-irregardless-grammar-peeve-blend-of-the-synonyms-irrespective-and-regardless

Irregardless

It is in fact a real word (but that doesn't mean you should use it).

video-moose-goose-weird-plurals

Weird Plurals

One goose, two geese. One moose, two... moose. What's up with that?

Word Games

stylized-drawing-of-woman-pole-vaulting-across-gap-to-get-trophy

Challenging Vocabulary Quiz Returns!

No tricks, just difficult words.

Take the quiz

Name that Color!

NEW! Additional colors! More obscure than before!

Take the quiz

How Strong Is Your Vocabulary?

How Strong Is Your Vocabulary?

Test your vocabulary with our 10-question quiz!

Take the quiz

Word Winder's CrossWinder

Word Winder's CrossWinder

A game of winding words.

Play the game