Unpleasantness

wiktionary

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From unpleasant +‎ -ness.

etymonline

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unpleasantness (n.)

1540s, "state or quality of being unpleasant," from unpleasant + -ness. By 1835 as "a slight quarrel, a minor misunderstanding." The late unpleasantness as a humorously polite Southern description of the American Civil War is attested from 1868.