Something striking grabs your attention because it’s vivid and surprising. Many twins have a striking resemblance. People in red satin evening gowns, the pyramids in Egypt, and platform heels with fish in them are also striking.
Anything striking is hard not to notice; it almost hits, or strikes, you with surprise, like a toddler in a tuxedo. People can be striking, and so can landscapes — one of the most striking sights in the world is the Grand Canyon, which is why so many people visit just to look at it. Non-visual things can be striking too, like a striking thought that makes you shout, “Eureka!”