sev·en·ty 
/ˈsɛvənti/ noun
plural sev·en·ties /ˈsɛvənti/ noun 1 [count] : the number 70 2 seventies [plural] a : the numbers ranging from 70 to 79
▪ a salary in the low seventies [=between $70,000 and $74,000]
b : a set of years ending in digits ranging from 70 to 79
▪ She grew up in the seventies. [=1970–1979] ▪ She is in her seventies.
▪ a salary in the low seventies [=between $70,000 and $74,000]
b : a set of years ending in digits ranging from 70 to 79
▪ She grew up in the seventies. [=1970–1979] ▪ She is in her seventies.
— sev·en·ti·eth /ˈsɛvəntijəθ/ noun, plural sev·en·ti·eths [count]
▪ one seventieth of the total
/ˈsɛvəntijəθ/ noun, plural sev·en·ti·eths [count] ▪ one seventieth of the total
— seventieth adjective
▪ his seventieth birthday
▪ his seventieth birthday
— seventy adjective
▪ seventy books
▪ seventy books
— seventy pronoun
▪ Seventy (of them) came to the performance. ▪ seventy of her classmates
▪ Seventy (of them) came to the performance. ▪ seventy of her classmates
