[ ep-uh-thee-lee-uhm ]

noun,plural ep·i·the·li·ums, ep·i·the·li·a [ep-uh-thee-lee-uh]. /ˌɛp əˈθi li ə/. Biology.
  1. any plant or animal tissue that covers a surface or lines a cavity, and that also performs any of various secretory, transporting, or regulatory functions.

Origin of epithelium

First recorded in 1740–50; from New Latin, from Greek epi- epi- + thēl(ḗ) “teat” + New Latin -ium -ium

Other words from epithelium

  • ep·i·the·li·al, adjective

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How to use epithelium in a sentence

British Dictionary definitions for epithelium


/ (ˌɛpɪˈθiːlɪəm) /

nounplural -liums or -lia (-lɪə)
  1. an animal tissue consisting of one or more layers of closely packed cells covering the external and internal surfaces of the body. The cells vary in structure according to their function, which may be protective, secretory, or absorptive

Origin of epithelium

C18: New Latin, from epi- + Greek thēlē nipple

Derived forms of epithelium

  • epithelial, adjective

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for epithelium


[ ĕp′ə-thēlē-əm ]

Plural epithelia
  1. The thin, membranous tissue that lines most of the internal and external surfaces of an animal's body. Epithelium is composed of one or more layers of densely packed cells. In vertebrates, it lines the outer layer of the skin (epidermis), the surface of most body cavities, and the lumen of fluid-filled organs, such as the gut or intestine.

Other words from epithelium

  • epithelial adjective

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