nemesis
UK: ˈnɛmɪsɪs | US: ˈnɛməsɪs
n. 1. A long-standing rival or archenemy; one who inflicts retribution or vengeance.
n. 2. (Greek mythology) The goddess of retributive justice or vengeance.
n. 3. A source of persistent frustration or defeat.
Derived directly from Greek Nemesis (Νέμεσις), the name of the goddess who personified divine retribution against hubris. The root neme- relates to "distribution" or "just allotment" (from nemein, "to distribute"). Over time, the word evolved into English to signify an inescapable agent of downfall or punishment, reflecting the goddess's role in myth. The suffix -sis (as in "thesis" or "analysis") marks it as a noun of action or condition.
The detective finally confronted his nemesis in a climactic showdown.
In Greek tragedies, hubris often invites the wrath of Nemesis.
Procrastination became her nemesis during exam season.
The team's nemesis, the defending champions, defeated them again.
He viewed the challenging puzzle as his intellectual nemesis.