By his assiduousness the work was recommenced this same year, and on the 5th of August, 1858, was completed.
From the latter assiduousness is reached and, finally, Great Services.
1530s, from Latin assiduus "attending; continually present, incessant; busy; constant," from assidere "to sit down to," thus "constantly occupied" at one's work; from ad "to" (see ad-) + sedere "to sit" (see sedentary). The word acquired a taint of "servility" in 18c. Related: Assiduously; assiduousness.