assiduate

from The Collaborative International Dictionary of English v.0.48

Assiduate \As*sid"u*ate\, a. [L. assiduatus, p. p. of assiduare
   to use assiduously.]
   Unremitting; assiduous. [Obs.] "Assiduate labor." --Fabyan.
   [1913 Webster]