Meaning of top hat

top' hat"

Pronunciation: [key]
  1. a tall, cylindrical hat with a stiff brim usually slightly curved on the sides, worn by men esp. on formal occasions. Cf. (def. 4),

top-hat

Pronunciation: (top'hat'), [key]
— adj.
  1. of or pertaining to polite or fashionable society.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.