/ˈbɔːrdər ˈmɑːrkər/ – Phrase
Definition: cột mốc biên giới.
A more thorough explanation: A border marker is a physical object or structure, such as a stone, post, or monument, that is placed along a boundary line to indicate the limits of a specific territory or jurisdiction. Border markers are used to define and demarcate the borders between countries, states, or other political subdivisions, and are often established and maintained in accordance with legal agreements or regulations.
Example: The surveyor placed a border marker to clearly delineate the boundary between the two properties.