1. to cause severe physical or mental pain or suffering
Usage: British spelling; American spelling is 'agonizes'; transitive verb
2. to struggle or worry intensely about something
Usage: British spelling; American spelling is 'agonizes'; intransitive verb, often followed by 'over' or 'about'

Examples

• The injury agonises him whenever he tries to move his arm.
• She agonises over every decision before making a choice.
• The guilt agonises his conscience day and night.
• He agonises about whether he made the right career decision.
• The pain agonises the patient despite the medication.
• They agonise over the ethical implications of the project.