gyroscope (n.) Look up gyroscope at
heavy rotating wheel with an axis free to turn in any direction, 1853, improved and named in French 1852 by Foucault, from Greek gyros "a circle" (see gyre (n.)) + skopos "watcher" (from PIE root *spek- "to observe"), because the device demonstrates that the earth rotates.
gyroscopic (adj.) Look up gyroscopic at
1869, from gyroscope + -ic. Related: Gyroscopically.
gyrostat (n.) Look up gyrostat at
instrument for illustrating the dynamics of rotation, 1868, from gyro- + -stat.
gyrostatics (n.) Look up gyrostatics at
branch of dynamics dealing with rotating bodies, 1883, from gyrostatic (1875); see gyrostat + -ics.
gyrus (n.) Look up gyrus at
convolution between grooves of the brain, 1827, from Latin gyrus "circle, circuit, career," from Greek gyros "a ring, circle" (see gyre (n.)).