it's come to have more senses than given in that 1913 entry; but still, it's related to feminine (but not to be confused with effeminate).

Etymology: Latin effetus, from ex- + fetus pregnant, breeding, fruitful -- more at FEMININE
1 : exhausted of fertility : no longer able to produce young or fruit : UNFRUITFUL <eroded effete earth>
2 : marked by lack or deprivation of some inherent characteristic : ENERVATED: a of a substance : having lost its unique quality (as flavor) b : exhausted of physical energy : worn out : SPENT <effete, weary, burned-out revolutionists -- H.F.Mooney> c : having lost character, courage, strength, stamina, or vitality <effete literary critics and dogmatic professors -- J.T.Farrell> : DEGENERATE <a soft, effete, and decadent race -- R.P.Parsons> d : totally devoid of an original positive drive or purposiveness <vaguely educated for minor diplomatic or other governmental posts in an effete struggle to maintain position -- Janet Flanner> e : soft or decadent as a result of overrefinement of living conditions or laxity of mental or moral discipline <the effete householder who wants things done for him -- New Yorker> <the effete gentility that lay like a blight on the critical writing of the nineties -- C.I.Glicksberg> f : OUT-OF-DATE, OUTMODED <an old but by no means effete statute -- Edward Jenks>
-Webster's Third New International Dictionary, Unabridged