The term 'BASSOONIST'S BUY' is a crossword solution that consists of two words. The first word, 'REED', is a four-letter word that refers to the thin strips of cane or synthetic material that are used to make the reeds for a bassoon. The second word, 'BUY', is a three-letter word that refers to the purchase of the reeds by a bassoonist. Therefore, the crossword solution 'BASSOONIST'S BUY' can be interpreted as the act of a bassoonist buying reeds for their instrument.