数すう十じゅう年ねん

noun, adverb

several decades; many decades; a few decades

Refers to a period of roughly 20 to 90 years, often used when the exact number is unknown or not specified. Can be used as a noun or adverbially.

• この町まちは数すう十じゅう年ねんで大おおきく変かわった。

  This town has changed greatly over several decades.

• 数すう十じゅう年ねんぶりに故こ郷きょうに帰かえった。

  I returned to my hometown for the first time in decades.