Emulation, n.
Etymology: [L. aemulatio: cf. F. émulation.]
1. The endeavor to equal or to excel another in qualities or actions; an assiduous striving to equal or excel another; rivalry. A noble emulation heats your breast. Dryden.
2. Jea Such factious emulations shall arise. Shak.
Syn. -- Competition; rivalry; contest; contention; strife. -- Emulation, Competition, Rivalry. Competition is the struggle of two or more persons for the same object. Emulation is an ardent desire for superiority, arising from competition, but now implying, of necessity, any improper feeling. Rivalry is a personal contest, and, almost of course, has a selfish object and gives rise to envy. "Competition and emulation have honor for their basis; rivalry is but a desire for selfish gratification. Competition and emulation animate to effort; rivalry usually produces hatred. Competition and emulation seek to merit success; rivalry is contented with obtaining it." Crabb.
Shades of meaning
Fernald has no entry of its own for emulation; he lists it under ambition.
Where he writes about it:
Emulation is not so much to win any excellence or success for itself as to equal or surpass other persons. — from ambition
There is such a thing as a noble emulation, when those we would equal or surpass are noble, and the means we would use worthy. — from ambition
But, at the highest, emulation is inferior as a motive to aspiration, which seeks the high quality or character for its own sake, not with reference to another. — from ambition
Emulation regards the abstract, competition the concrete; rivalry is the same in essential meaning with competition, but differs in the nature of the objects contested for, which, in the case of rivalry, are usually of the nobler sort and less subject to direct gaging, measurement, and rule. — from ambition
We speak of competition in business, emulation in scholarship, rivalry in love, politics, etc.; emulation of excellence, success, achievement; competition for a prize; rivalry between persons or nations. — from ambition