Lewis & Short

aemŭlātus, ūs, m. Perh. only in Tac. for the class. aemulatio, emulation, rivalry, Hist. 3, 66.
In plur., Ann. 13, 46. (But in Agr. 46, aemulatu is only a conjecture of Heinsius; Orell. and Halm read similitudine).