Main Entry: dark age

Function: noun

Date: 1640

1 : a time during which a civilization undergoes a decline: as a plural capitalized D&A : the European historical period from about a.d. 476 to about 1000; broadly : middle ages b often plural often capitalized D&A : the Greek historical period of three to four centuries from about 1100 b.c.
2 a often plural often capitalized D&A : the primitive period in the development of something <in the dark ages of medicine> b often plural often capitalized D&A : a state of stagnation or decline