'Bitter' in the Bible

It is one who is by himself, without a second, and without son or brother; but there is no end to all his work, and he has never enough of wealth. For whom, then, am I working and keeping myself from pleasure? This again is to no purpose, and a bitter work.

And I saw a thing more bitter than death, even the woman whose heart is full of tricks and nets, and whose hands are as bands. He with whom God is pleased will get free from her, but the sinner will be taken by her.