big top

noun
1.
the largest or main tent of a circus.
2.
a circus.
Origin
1890-95, Americanism
British Dictionary definitions for big top

big top

noun (informal)
1.
the main tent of a circus
2.
the circus itself
Idioms and Phrases with big top

big top

.
The main tent of a circus, as in The high-wire act is almost always in the big top. [ c. 1840 ]
.
Underworld slang for a maximum-security prison, as in He was sentenced to ten years in the big top. [ 1950s ]