The definition of a foe is an enemy or opponent.
(noun)A person who you are always trying to defeat in games is an example of your foe.
See foe in Webster's New World College Dictionary
noun
Origin: ME fo, ifo < OE fah, hostile, (ge)fah, enemy, akin to OHG gefēh, at feud, hostile: for IE base see feud
See foe in American Heritage Dictionary 4
noun
Origin:
Origin: Middle English fo
Origin: , from Old English gefā
Origin: , from fāh, hostile
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