|a printed punctuation mark (‽), available only in some typefaces, designed to combine the question mark (?) and the exclamation point (!), indicating a mixture of query and interjection, as after a rhetorical question.|
|a children's mummer's parade, as on the Fourth of July, with prizes for the best costumes.|
|—n , pl -liums, -lia|
|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|
|[C18: New Latin, from |
epithelium ep·i·the·li·um (ěp'ə-thē'lē-əm)
n. pl. ep·i·the·li·ums or ep·i·the·li·a (-lē-ə)
Membranous tissue composed of one or more layers of cells separated by very little intercellular substance and forming the covering of most internal and external surfaces of the body and its organs.
|epithelium (ěp'ə-thē'lē-əm) Pronunciation Key
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.
in anatomy, layer of cells closely bound to one another to form continuous sheets covering surfaces that may come into contact with foreign substances. Epithelium occurs in both plants and animals
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