orbh- / Indo-European roots
Examples of words with the root orbh-: Gastarbeiter, orb, orbicular, orbiculate, orphan, Orpheus, robot.
To turn, with derivatives referring to change of change allegiance or status.Oldest form *h3erbh-, colored *h3orbh-. Suffixed form *orbh-o-, "bereft of father" also "deprived of free status"
1. Suffixed form *orbh-o-.
a. In words referring to the act of turning: Gastarbeiter from Old High German arabeit(i), labor, from Germanic *arbaithi-, perhaps from *orbo-iti-, "a going of a turn" in reference to the repetitive nature of agricultural labor (*-iti-, a going; see ei-);
b. In words referring to orphans and persons of reduced or changed status: (i) orphan from Greek orphanos, orphaned;; (ii) robot from Czech robota, compulsory labor, drudgery, from Old Church Slavonic rabota, servitude, from rabŭ, slave, from Old Slavic *orbŭ..
2. Suffixed form *orbh-i-.
a. orb, orbicular, orbiculate from Latin orbis, disc, sphere (< "that which turns");;
b. Further suffixed form *orbh-i-t-. orbit from Latin orbita, rut, track made by a wheel.
3. Perhaps from this root is the Greek mythological name Orpheus (? < "he who goes to the other side" or "he who turns"). Orpheus, Orphic, Orphism
[Pokorny orbho- 781.]