The term "stereotactic" is a modern scientific coinage, combining two Greek-derived elements to describe a precise spatial technique. The first part, "stereo-", originates from the Greek stereos, meaning "solid," which evolved to imply three-dimensionality, as a solid object occupies space in three dimensions. The second part, "-tactic," derives from the Greek taktikos, relating to arrangement or order, itself from the verb tassein, meaning "to arrange" or "to draw up in ranks." Thus, the literal construction means "pertaining to three-dimensional arrangement." This perfectly captures the method's essence: using a three-dimensional coordinate system to arrange or guide an instrument with extreme precision to a targeted point within the body, particularly the brain.

Structure: stereo (solid, three-dimensional) + tactic (arrangement, order) - stereo: From Greek stereos, meaning "solid, firm, three-dimensional." In this word, it denotes three-dimensional space. - tactic: From Greek taktikos, meaning "of or relating to arrangement or order," from tassein "to arrange." In this word, it refers to precise spatial arrangement or positioning.