The term 'burn a perfume stick in' can be summarized by the five-letter word 'CENSE, ' which is derived from the verb 'to censer, ' meaning to burn incense. Incense is a type of fragrant material, usually made from plant resins, that is burned to produce a pleasant aroma. Burning incense is a common practice in many cultures and religions, and is often used in religious ceremonies or for spiritual purposes.