Effusive rocks

effusive \ef*fu"sive\, a.
   1. Pouring out; pouring forth freely. [archaic] "Washed with
      the effusive wave." --Pope.
      [1913 Webster]

   2. (Geol.) formed by an outpouring of molten lava, or
      pertaining to rocks so formed.
      [PJC]

   3. overly demonstrative; expressing emotion in an
      unrestrained manner; exhibiting unrestrained enthusiasm;
      -- of people and human actions; as, effusive thanks; an
      effusive letter of recommendation. Contrasted with
      {reserved}. [WordNet sense 1+2]

   Syn: gushing, gushy, burbling, burbly. [PJC]

   {Effusive rocks} (Geol.), volcanic rocks formed by a
      nonexplosive outpouring of lava in molten or plastic form;
      in distinction from so-called {intrusive}, or {plutonic},
      rocks. -- {Ef*fu"sive*ly}, adv. -- {Ef*fu"sive*ness}, n.
      [1913 Webster]