As`si*du"i*ty (#), n.; pl. Assiduities (#). [L. assiduitas: cf. F. assiduite. See Assiduous.]
Constant or close application or attention, particularly to some business or enterprise; diligence.
I have, with much pains and assiduity, qualified myself for a nomenclator.
Studied and persevering attention to a person; -- usually in the plural.
© Webster 1913.