Meaning of GYRO- in English
a combining form meaning "ring," "circle," "spiral," used in the formation of compound words: gyromagnetic; gyroscope.
Also, esp. before a vowel, gyr- .
[ gyros ring, n. use of gyrós round ]
Random House Webster's Unabridged English dictionary. Полный английский словарь Вебстер - Random House . 2012