con·found 
(kən-found, kŏn-)
(kən-found, kŏn-)tr.v. con·found·ed, con·found·ing, con·founds
1. To cause to become confused or perplexed. See Synonyms at perplex.
2. To fail to distinguish; mix up: Don't confound fiction and fact.
3. To make (something bad) worse: Do not confound the problem by losing your temper.
4. To cause to be ashamed; abash: an invention that confounded the skeptics.
5. Used in mild curses: Confound you!
6.
a. To frustrate or thwart: trivial demands that confounded the peace talks.
b. Archaic To defeat or overthrow (an enemy).
[Middle English confounden, from Anglo-Norman confundre, from Latin cōnfundere, to mix together, confuse : com-, com- + fundere, to pour; see gheu- in the Appendix of Indo-European roots.]
con·founder n.
con·founding·ly adv.