noun
benchmark; bench mark
A fixed reference point used in surveying to measure elevation. Technical term.
測量士は水準点を基準にして標高を測った。
The surveyor measured the elevation based on the benchmark.
三角点 is a triangulation point used for horizontal positioning, while 水準点 is specifically for vertical elevation reference.
Compound of 水準 (water level, standard) and 点 (point). The term is a direct translation of the English 'benchmark' in a surveying context.