"DINK" is an acronym that stands for "double income, no kids" or "dual income, no kids", referring to couples who are voluntarily childless. It describes a couple without children living together while both partners are receiving an income; because both of their wages are coming into the same household, they are able to live more comfortable economically than couples who live together and spend their money on raising their children. The term was coined at the height of yuppie culture in the 1980s.

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"DINKY" means "double income, no kids yet", implying that the couple in question is childless only temporarily and intends to have children later, rather than eschewing having children entirely.