groves — a small wood or forested area, usually with no undergrowth: a grove of pines.
stems — science, technology, engineering, and mathematics, considered as a group of academic or career fields (often used attributively): degree programs in STEM disciplines; teaching STEM in high school.
pins — a number assigned to an individual, used to establish identity in order to gain access to a computer system via an automatic teller machine, a point-of-sale terminal, or other device.
boxes — an evergreen shrub or small tree of the genus Buxus, especially B. sempervirens, having shiny, elliptic, dark-green leaves, used for ornamental borders, hedges, etc., and yielding a hard, durable wood.