To beg means to ask for something desperately or humbly, often when you really need it and have no other way to get it. A person who has no money or home might beg for food or spare change on the street. A lost dog might sit and beg with its paws up, hoping for a treat.

The word suggests pleading, sometimes repeatedly, because what you want matters urgently to you. When you beg, you're expressing real need or strong desire, not making a casual request. A student might beg their teacher for one more day to finish a project. Your little brother might beg you to let him play with your favorite toy.

People also use “beg” in expressions. When something begs the question, it can mean that it raises an obvious question that needs answering. In careful logic, it can also mean that someone is assuming the very thing they are trying to prove. If you say “I beg to differ,” you're politely disagreeing with someone.

A person who begs is called a beggar. There's an old saying: “Beggars can't be choosers,” meaning that when you're asking for help, you should gratefully accept whatever you're offered rather than being picky about it.