seventieth/ˈsɛvnti.əθ/EtymologyFrom earlier seventeth, from Middle English seventiþe, seventithe; equivalent to seventy + -eth. For the modern form, see the etymological notes at twentieth.seventieth means The ordinal form of the number seventy. Lexicurio rates it Rare gem — a strength score of 79 out of 100.adjThe ordinal form of the number seventy.nounThe person or thing in the seventieth position.“All the septuagenarians remembered their seventieths fondly.”One of seventy equal parts of a whole.