cum·shaw /ˈkʌmʃɔ/
a present; gratuity; tip.

[Origin: 1810-20; < dial. Chin (Xiamen) kam siā, equiv. to Chin gân xiè grateful thanks]


Customs went over the ship as if they were expecting loose diamonds to have rolled into the seams in the decking…. He suspected – that nasty Takisian-born cynicism again – they were really scouting for cumshaw.

Source: Turn of the Cards, Victor Milán.