Price Gap
Also called: gap up, gap down, gap fill
A gap is a jump between one session's close and the next session's open with no trading in between, usually caused by news released outside market hours. Gaps are the reason a stop-loss is not a guarantee: an order to sell at $50 executes at $42 if the stock opens there. The folk belief that gaps always fill is true often enough to be dangerous and false often enough to ruin someone.