society > morality > duty or obligation > [adjective] > due or owed (of an obligation) > falling upon one as a duty (4)
With to or simple complement. Incumbent upon a person as a duty. Obsolete.
Resting or falling upon a person as a duty or obligation. Const. on, upon, (also †to).
Relating to duty or obligation. Obsolete. rare.
Useful, profitable, advantageous; incumbent.