staircases is a form of:

Staircase



noun
1.
(a flight of stairs (often with banisters) and its supporting structure) ជណ្ដើរនិងបង្កាន់ដៃ, ម៉ាស៊ីន
ENGLISH MEANING
noun
1.
A flight of stairs with their supporting framework, casing, balusters, etc.