alto-rilievo \al"to-rilievo\, n.; pl. alto-rilievos. it.
   sculp.
   high relief; sculptured work in which the figures project
   more than half their thickness; as, this figure is an
   alto-rilievo or in alto-rilievo.
   1913 webster

   note: when the figure stands only half out, it is called
         mezzo-rilievo, demi-rilievo, or medium relief; when its
         projection is less than one half, basso-rilievo,
         bas-relief, or low relief.
         1913 webster altostratus
see also:
alto-rilievos