DINK is an acronym that stands for "Dual Income, No Kids." It describes a couple who both work and do not have children.Image cropped for size from the original at imgur.
DINKER means "Dual (or Double) Income & No Kids Early Retirement."
DINKY means "Double Income, No Kids Yet."
GINK means "Green Inclinations, No Kids" - referring those who choose not to have children for environmental reasons.