The plural of terminus is termini or terminuses.
Terminus refers to the final point or end of a transportation route, journey, or line. It is often associated with transportation systems such as railways, bus routes, and subway lines. The terminus marks the endpoint or destination of the route, where passengers or cargo disembark or where the transportation vehicle is turned around.
The graph shows the occurances of the plural of terminus in written English since 1800 using Google's Ngram Viewer.
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