From WordNet (r) 2.0 (August 2003) [wn]:
Capitol
n 1: the federal government of the United States [syn: Capitol,
Washington]
2: the government building in Washington where the United
States Senate and the House of Representatives meet [syn:
Capitol, Capitol Building]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Capitol \Cap"i*tol\, [L. capitolium, fr. caput head: cf. F.
capitole. See Chief.]
[1913 Webster]
1. The temple of Jupiter, at Rome, on the Mona Capitolinus,
where the Senate met.
[1913 Webster]
Comes C[ae]sar to the Capitol to-morrow? --Shak.
[1913 Webster]
2. The edifice at Washington occupied by the Congress of the
United States; also, the building in which the legislature
of a State holds its sessions; a statehouse.
[1913 Webster] Capitolian