noun
Refers to the farthest end or edge of something, often in a spatial or sequential sense. Commonly used with の to modify a noun.
彼は列の一番端に立っていた。
He was standing at the very end of the line.
その本は棚の一番端に置いてある。
The book is placed at the very edge of the shelf.
先端 often refers to the tip or cutting edge of something, especially in technology or physical objects, whereas 一番端 is more about the farthest point in a sequence or arrangement.
Compound of 一番 (number one, most) and 端 (end, edge). The combination straightforwardly means 'the very end'.