also: とったん
noun
tip of a cape; point of a headland
Refers specifically to the very end of a geographical promontory or cape. Not used for general 'point' or 'tip' of objects.
岬の突端に灯台が立っている。
A lighthouse stands at the tip of the cape.
地図で見ると、突端の部分が細長く伸びている
Looking at the map, the tip of the headland stretches out long and narrow.
Compound of 突 (thrust, protrude) and 端 (end, tip). The reading とっぱな is a euphonic change from とったん, with はな being a common reading for 端 in such compounds.