endothelium endotheliotoxin • endotherm knife · · · Info · Definitions · Characters · · endothelium · · Text Latin · · Script 11 · · Length 5 · · Syllables Definitions · · · (noun) an epithelium of mesoblastic origin; a thin layer of flattened cells that lines the inside of some body cavities. · · Noun Definition 1 Characters · · d latin small letter d U+0064 e latin small letter e U+0065 h latin small letter h U+0068 i latin small letter i U+0069 l latin small letter l U+006C m latin small letter m U+006D n latin small letter n U+006E o latin small letter o U+006F t latin small letter t U+0074 u latin small letter u U+0075