To agonize means to worry intensely about something or to struggle painfully with a difficult decision. When you agonize over a choice, you think about it again and again, weighing every possibility, imagining what might go wrong, and feeling real mental distress about getting it right.

A student might agonize over whether to try out for the school play or join the soccer team, spending days thinking through each option. A writer might agonize over the perfect ending for her story, rewriting it multiple times because she cares so deeply about getting it just right. The word suggests genuine suffering or torment, a state of serious distress beyond casual thinking.

Agonize comes from the Greek word for struggle or contest, and it carries that sense of wrestling with something difficult. When you agonize, you're in a mental battle. You might lie awake at night, talk through the problem endlessly with friends, or make lists of pros and cons that never quite settle the question.

Notice that agonizing is different from simply making a choice. It's that extended period of anxiety and overthinking before you decide. Sometimes we agonize over decisions that turn out fine either way, which is why people sometimes advise, “Don't agonize over it,” when a choice doesn't have one clearly wrong answer.