Staircase \Stair"case`\, n. A flight of stairs with their supporting framework, casing, balusters, etc.

To make a complete staircase is a curious piece of architecture. --Sir H. Wotton.

Staircase shell. (Zo["o]l.)
   (a) Any scalaria, or wentletrap.
   (b) Any species of Solarium, or perspective shell.

Source: Webster's Revised Unabridged Dictionary (1913)