The term PESTLE PARTNER is a crossword solution that is composed of two words: PESTLE and MORTAR. Pestle is a tool used in grinding and mixing substances, while MORTAR is a mixture of sand, cement, and water used in construction. Together, they form a partnership in which the pestle is used to grind and mix ingredients, while the MORTAR is used to hold them together. This partnership is essential in many construction projects, as it allows for the creation of strong and durable structures.