Pronunciation: [ nem-uh-sis ]
1: something that a person cannot conquer, achieve, etc.
2: an opponent or rival whom a person cannot best or overcome
Origin: Late 16th century; Greek
Etymology: Greek, literally ‘retribution’, from nemein ‘give what is due’
Example: 1: The running test was consistently the team's nemesis.
2: The Joker was Batman's nemesis.