Something that shares a boundary or limit with something else; bordering or delimiting.
From con- + terminant (something that terminates or bounds), from Latin terminus. A variant or related form of conterminal, less commonly used.
This is the rarer sibling of conterminal—most texts prefer the -al form, but conterminant appears occasionally in older philosophical and mathematical writing where authors wanted to emphasize something actively forming a boundary rather than passively sharing one.
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