Dictionary.com/discomfit (etymology):

discomfit (dis-KUHM-fit; dis-kuhm-FIT) transitive verb

1. To make uneasy or perplexed; disconcert. See Synonyms at embarrass.
2. To thwart the plans of; frustrate.
3. Archaic. To defeat in battle; vanquish.

Source: The American Heritage® Dictionary of the English Language, Fourth Edition
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