cyclorama
Concise Oxford English Dictionary © 2008 Oxford University Press:
cyclorama /ˌsʌɪkləˈrɑːmə/
▶noun
- 1 a panoramic scene set on the inside of a cylindrical surface, to be viewed by a central spectator.
- 2 a cloth stretched tight in an arc around the back of a stage set, often used to represent the sky.
– derivatives
cycloramic /-ˈramɪk/ adjective.
cycloramic /-ˈramɪk/ adjective.
'cyclorama' also found in these Oxford entries:

