To queue-jump is to go in front of people who have been waiting in a line when it is not your turn. In British English the line is a queue, so this is their everyday verb; in American English people usually say cut in line. It is always a complaining word — nobody says it as praise. Though actually, people stretch it a long way: if someone rich or well-connected gets a house, a hospital date, or a school place before people who waited longer, news writers still say they queue-jumped, even when there is no physical line at all. The unfair “before other people” feeling is the heart of the word. In Taiwan the same idea is 插隊, and people feel it just as strongly in a shop or at a ticket window.