Execute
To complete; to make; to sign; to perform; to do; to carry out according to its terms; to fulfill the command or purpose of. To perform all necessary formalities, as to make and sign a contract, or sign and deliver a note.
Execute is the opposite of executory, incomplete or yet to be performed.
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Law Library - American Law and Legal InformationFree Legal Encyclopedia: Estate for years to Ex proprio motu (ex mero motu)