Unexpected delight is a feeling of joy or pleasure that is not expected. It can be caused by a surprise, a pleasant event, or a kind gesture. The term 'unexpected delight' can be summed up in the five-letter word 'TREAT'. A TREAT is something special that is given to someone as a reward or surprise. It can be a physical item, such as a gift or a snack, or it can be an experience, such as a trip or a day out.