hornstone hornstay • hornswoggle · · · Info · Definitions · Synonyms · Characters · · hornstone · · Text Latin · · Script 9 · · Length Definitions · · · (noun) a fine-grained metamorphic rock formed by the action of heat on clay rocks. Synonyms: hornfels. · · Noun Definition 1 Synonyms · · · hornfels · · Synonym 1 Characters · · e latin small letter e U+0065 h latin small letter h U+0068 n latin small letter n U+006E o latin small letter o U+006F r latin small letter r U+0072 s latin small letter s U+0073 t latin small letter t U+0074