A cudgel is a short, thick stick or club used as a weapon. Picture a heavy wooden club, usually about the length of your forearm, that someone might carry for protection or use in a fight. In medieval times and earlier, cudgels were common weapons for ordinary people who couldn't afford swords.

The word often appears in old stories and historical accounts. In Oliver Twist, the villain Bill Sikes carries a cudgel. Guards might threaten prisoners with cudgels, or bandits might attack travelers using them. A cudgel is blunt and brutal, nothing like the elegant swords of knights in stories.

Cudgel can also be a verb. You might hear the expression “to cudgel your brains,” which means to think really hard about something difficult. When you cudgel your brains trying to remember where you left your homework or puzzle through a challenging math problem, you're describing intense mental effort, as if you were striking at a problem until it gives way.