Senses
不当/ 不當 inappropriate
unsuitable; improper; not fitting
不当/ 不當 unfitting
(literary) poorly timed; not at the right time
不当/ 不當 should not
(literary) ought not to; should not
不当/ 不當 not count as
(literary) to not be considered as; to not count as
不当/ 不當 not be
(literary) to not be; it is not the case that