DEFINITION: To do. Oldest form *werg-, becoming *werg- in centum languages.
Derivatives include work, allergy, surgery, wrought, and orgy.
I. Suffixed form *werg-o-.
1a. work; handiwork, from Old English weorc, werc, work; b. boulevard, bulwark, from Old High German werc, work. Both a and b from Germanic *werkam, work.
2. erg, ergative, –urgy; adrenergic, allergy, argon, cholinergic, demiurge, dramaturge, endergonic, endoergic, energy, ergograph, ergometer, ergonomics, exergonic, exergue, exoergic, georgic, hypergolic, lethargy, liturgy, metallurgy, surgery, synergid, synergism, thaumaturge, from Greek ergon, work, action.
II. Zero-grade form *wig-. 
1. Suffixed forms *wig-yo-, *wig-to-. a. wrought, from Old English wyrcan, to work; b. irk, from Old Norse yrkja, to work. Both a and b from Germanic *wurkjan, to work, participle *wurhta-.
2. Suffixed form *wig-t-. wright, from Old English wryhta, maker, wright, from Germanic *wurhtj-.
III. O-grade form *worg-.
a. organ, organon, from Greek organon (with suffix -ano-), tool; b. orgy, from Greek orgia, secret rites, worship (< “service”). (Pokorny 2. uerg- 1168.)

Pagan sacred site of Uplistsikhe

(Uplistsikhe, Georgia)
Ten kilometers east of the village of Gori and two kilometers from a portion of the ancient Silk Road, the cave city of Uplistsikhe (pronounced oop-lis-si-hee) was a functioning city by late Bronze Age times of 1000 BC.
Severe erosion has damaged the site making archaeological excavation difficult and it is probable that the many naturally occurring caves had been inhabited at a far earlier age.
Prior to the introduction of Christianity to Georgia in the 4th century, Uplistsikhe was a prominent pagan holy place and the 9th century brick church of Uplistulis Eklesia (Prince's Church) was built directly over a pagan sun temple. During the early Middle Ages, when the city was at its peak of development, there was a population of perhaps 20,000 living in the 700 caves (of which only 150 remain). In the 13th century Mongol invasions devastated the city and a series of earthquakes contributed to its eventual abandonment.