Definitions

1. adjective

having the same duration or extent in time, or the same geographical area

“The new tax law will be coterminous with the current budget year.”

2. noun

a period of time that is shared by two or more things, especially by a government or an organization

“The coterminous period for the new project will begin on January 1.”

3. adverb

in the same time period or geographical area

“The new policy will be implemented coterminous with the existing system.”