From bi- + tangential. <span class="searchmatch">bitangential</span> (not comparable) Relating to a bitangent. (geometry) Meeting a curve at the tangency points of its bitangents....
an article on: bitangent Wikipedia bitangent (plural bitangents) (mathematics) A line that is tangent to a curve at two points <span class="searchmatch">bitangential</span> battening...