The Collaborative International Dictionary of English v.0.48:

Gravity \Grav"i*ty\, n.; pl. Gravities. [L. gravitas, fr.
   gravis heavy; cf. F. gravit['e]. See Grave, a., Grief.]
   1. The state of having weight; beaviness; as, the gravity of
      lead.
      [1913 Webster]

   2. Sobriety of character or demeanor. "Men of gravity and
      learning." --Shak.
      [1913 Webster]