Delay is when you or something (eg. A parcel) is late due to unexpected circumstances E.g - The doctors appointment was delayed by 30 minutes because the patient arrived late. Extend is when the time frame of the event is lengthened E.g - Lockdown was extended by another 3 months due to cases increasing. Reschedule is when you change the date of an event to another time E.g - The birthday party was rescheduled to be on the 3rd of February instead, as the child had caught a cold. Postpone can be used interchangeably with delay, but is usually used for when the delay is a longer period of time. E.g - I postponed my doctors appointment as I would be busy that day.