The decade of one's life from age 70 through age 79.(noun)
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Use "seventies" in a sentence
"I know that the first thing I think about when I remember the seventies is the Fairchild F-8 microprocessor."
"They are excellent and I have noticed no problems when it comes to covering women writers - the latest volume, covering the seventies, is certainly sympathetic when it covers the rise of feminism in SF: clearly he has no intellectual problem with women in SF."
"Most of my collection was levered off walls in the seventies from the top of precipitously-leaning ladders."