Definition of sugar-loaf:
(n) :
(historical) A block of refined sugar, usually in the form of a truncated cone, in which form it was traditionally exported from the Caribbean and Brazil from the 17th century to the 19th century.
(n) :
(obsolete) A hat shaped like a sugar-loaf.
(n) :
Ellipsis of sugar-loaf cabbage, a certain cultivar.
(n) :
Ellipsis of sugar-loaf chicory, a certain cultivar.