capillary action

noun

: capillarity sense 2

The liquid returns to the evaporation section of the heat pipe along a wick by means of capillary action.

—Science News, 22 July 1989

Word History

First Known Use

1809, in the meaning defined above

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!