Source : Webster's Revised Unabridged Dictionary (1913)

Imporosity \Im`po*ros"i*ty\, n. [Perf. im- not + porosity: cf.
   F. imporosit['e].]
   The state or quality of being imporous; want of porosity;
   compactness. ``The . . . imporosity betwixt the tangible
   parts.'' --Bacon.