The term 'buttonlike flower' is referring to the Tansy (5 letters). Tansy is a perennial herbaceous flowering plant of the aster family, native to temperate Europe and Asia. It has been introduced to other parts of the world, including North America, and in some areas has become invasive. The flowers are yellow, button-like, and produced in dense capitula. The leaves are pinnate, divided into multiple narrow segments. Tansy has a long history of use in traditional medicine and as an insect repellent.