defeater

verb (used with object)

1. to overcome in a contest, election, battle, etc.; prevail over; vanquish: They defeated the enemy. She defeated her brother at tennis.
2. to frustrate; thwart.
3. to eliminate or deprive of something expected: The early returns defeated his hopes of election.
4. Law. to annul.

noun

5. the act of overcoming in a contest: an overwhelming defeat of all opposition.
6. an instance of defeat; setback: He considered his defeat a personal affront.
7. an overthrow or overturning; vanquishment: the defeat of a government.
8. a bringing to naught; frustration: the defeat of all his hopes and dreams.
9. the act or event of being bested; losing: Defeat is not something she abides easily.
10. Archaic. undoing; destruction; ruin.

verb (tr)

1. to overcome in a contest or competition; win a victory over
2. to thwart or frustratethis accident has defeated all his hopes of winning
3. law to render null and void; annul

noun

4. the act of defeating or state of being defeated
5. an instance of defeat
6. overthrow or destruction
7. law an annulment

n.

1590s, from defeat (v.).

v.

late 14c., from Anglo-French defeter, from Old French desfait, past participle of desfaire “to undo,” from Vulgar Latin *diffacere “undo, destroy,” from Latin dis- “un-, not” (see dis-) + facere “to do, perform” (see factitious). Original sense was of “bring ruination, cause destruction.” Military sense of “conquer” is c.1600. Related: Defeated; defeating.