- dullness, dulness, obtuseness - the quality of being slow to understand
--1 is a kind of stupidity
--1 has particulars: oscitancy, oscitance - dullness, dulness - the quality of lacking interestingness
--2 is a kind of uninterestingness
--2 has particulars:boringness, dreariness; tediousness, tedium, tiresomeness; jejunity, jejuneness, tameness, vapidity, vapidness - dullness, dulness - a lack of visual brightness
--3 is a kind of visual property
--3 has particulars:dimness, subduedness; flatness, lusterlessness, lustrelessness, mat, matt, matte - dullness, dulness, bluntness - without sharpness of edge or point
--4 is a kind of shape, form, configuration, contour, conformation
--4 has particulars: obtuseness