'Grievous' in the Bible

Yahweh shall strike you with grievous boils on the knees and on the upper thighs [from which] {you will not be able to be healed}, from the sole of your foot and up to your crown.

then Yahweh shall overwhelm [you] with your plagues and the plagues of your offspring, severe plagues and lasting illnesses, grievous and enduring.

I applied my mind to seek and to search by wisdom all that is done under the heavens. It [is] a grievous task God has given to {humans}.

So I hated life because the work done under the sun [is] grievous to me. For everything [is] vanity and chasing wind!

There is a grievous evil which I have seen under the sun: wealth {hoarded} by its owner to his harm.

This also [is] a grievous illness. Exactly as he came, so he will go. What profit [does] he gain for all his toil for the wind?

God gives a man wealth, possessions, and honor, so that he lacks nothing his heart desires; yet God does not enable him to enjoy it--instead someone else ends up enjoying it. This [is] vanity--indeed, it [is] a grievous ill!