A person who you are always trying to defeat in games is an example of your foe.
Taxes that were the foe of economic development.
Origin of foe
- Middle English fo from Old English gefā from fāh hostile
From American Heritage Dictionary of the English Language, 5th Edition
- Middle English fo 'foe; hostile', from earlier ifo 'foe', from Old English ġefāh 'enemy', from fāh 'hostile', from Proto-Germanic *faihaz (cf. Old Frisian fāch 'punishable', Middle High German gevēch 'feuder'), from Proto-Indo-European *peik/k̑- 'to hate, be hostile' (cf. Middle Irish oech 'enemy, fiend', Latin piget 'he is annoying', Lithuanian piktas ‘evil’, Albanian pis ‘dirty, scoundrel’).
- An acronym of fifty-one ergs