Definition of "songkok"

He saw himself, in a smart suit and a songkok, bowed into the opulent suites of Ritzes and Waldorfs and baring, under dark glasses, a hairy chest to a milder sun by a snakeless sea.

1958, Anthony Burgess, The Enemy in the Blanket (The Malayan Trilogy), published 1972, page 302

Short and thick set, he almost invariably dressed in a Western business suit or a safari jacket once he gave up his military uniform, and a black songkok, the flat traditional Indonesian cap.

2008 January 28, Marilyn Berger, “Suharto Dies at 86; Indonesian Dictator Brought Order and Bloodshed”, in New York Times‎