1943, in reference to grammatical case used for the subjects of transitive verbs (in Eskimo, Basque, Caucasian languages), from Greek ergatos "workman," from combining form of ergos "work" (from PIE root *werg- "to do") + -ive.
erection
erector
eremite
Erewhon
erg
ergative
ergo
ergonomics
ergophobia
ergot
ergotism