WordReference Random House Unabridged Dictionary of American English © 2026
per•i•the•li•um
(per′ə thē′lē əm),USA pronunciation n., pl. -li•a (-lē ə).USA pronunciation [Anat.]
per′i•the′li•al, adj.
- Anatomythe connective tissue surrounding certain small vessels, as capillaries.
- Neo-Latin, equivalent. to Greek peri- peri- + thēl(é̄) nipple + Latin -ium -ium
- 1875–80