fluid

adjective1 of 2

a material that can easily flow. e.g. water

• “Blood is the fluid responsible for the circulation of nutrients.”Tatoeba
• “The doctor tells me to drink plenty of fluids.”Tatoeba

Sentences from Tatoeba show real usage. A word can have several meanings, so a sentence may use another one.

noun2 of 2

Any substance which can flow with relative ease, tends to assume the shape of its container, and obeys Bernoulli's principle; a liquid, gas or plasma.