As nouns the difference between bitterness and hardship
is that bitterness is the quality of having a bitter taste while hardship is (countable or uncountable) Difficulty or trouble; hard times.
bitterness
English
Noun
the quality of having a bitter taste
the quality of feeling bitter; acrimony, resentment
Synonyms
* (quality of being bitter in taste) acerbicness, acridity, acridness
* (quality of feeling bitter) acrimony, gall, rancor/rancour, resentment
hardship
English
Noun
(
en noun)
(countable or uncountable) Difficulty or trouble; hard times.
- He has survived periods of financial hardship before.