Encarta:

outrival | outrivaled [past tense] | outrivaling [present participle] | outrivals [3rd-person singular present]

Summary:

to surpass somebody or something  (5 of 31 words, pronunciation)

Link:

http://encarta.msn.com/dictionary 701708307/definition.html  [cite]

Wiktionary:

outperform | outperformed [past tense] | outperforming [present participle] | outperforms [3rd-person singular present] | outrival [transitive verb] | outrivalled [transitive verb, past tense] | outrivaled [transitive verb, past tense] | outrivalling [transitive verb, present participle] | outrivaling [transitive verb, present participle] | outrivals [transitive verb, 3rd-person singular present]

Summary:

To perform better than something or someone.  (7 of 12 words, 1 etymology)

Link:

http://en.wiktionary.org/wiki/outperform  [cite]

Wikipedia:

Rival

Summary:

a person, team, company, or other organization competing against another person or team, etc. Rival or rivals may also refer to: "Rival" (Pearl Jam song), song on Pearl Jam's 2000's album Binaural | "Rival" (song), the second opening theme song of ...  (40 of 235 words, 16 senses)

Link:

http://en.wikipedia.org/wiki/Rival  [cite]

Random House:

rival | rivaled [past tense] | rivaling [past participle] | rivalled  [British, past participle] | rivalling [present participle]

Summary:

a person who is competing for the same object or goal as another, or who tries to equal or outdo another; competitor. | a person or thing that is in a ...  (30 of 129 words, 8 senses, pronunciation)

Link:

http://dictionary.infoplease.com/rival  [cite]

Merriam-Webster:

rival

Summary:

one of two or more striving to reach or obtain something that only one can possess | one striving for competitive advantage | obsolete; "companion", ...  (23 of 73 words, 4 senses, 1 etymology, pronunciation)

Link:

http://www.merriam-webster.com/dictionary/rival  [cite]