flapjack
A thick, fluffy pancake often served in a stack.
A flapjack is a pancake, especially one that's thick and fluffy. When you order flapjacks at a diner, you'll get a stack of golden-brown cakes cooked on a griddle, ready for butter and syrup.
In Britain, though, flapjack means something completely different: a chewy bar made from oats, butter, and syrup, baked until golden. British flapjacks are more like granola bars than pancakes. So if you're reading a British book and a character enjoys flapjacks with tea, picture a sweet oat bar, not a breakfast pancake.
In the United States, the pancake meaning is common. Picture a lumberjack at dawn, eating a tall stack of flapjacks before heading out to work. The word has an old-fashioned, hearty feeling, like something from a different era when breakfast was a serious meal and people had appetites to match.