[1615–25; extravag(ant) + -ancy]This word is first recorded in the period 1615–25. Other words that entered Englishat around the same time include: deposit, evolution, garrote, oral, trigger-ancy is a combination of -ance and -y, used to form nouns denoting state or quality. Other words that use the affix -ancy include: inerrancy, intendancy, mendicancy, occupancy, poignancy