How to say "decade" in Japanese

• 桁けたJLPT N2approx.Common
  nounThis is the technical 'decade' of science and mathematics: a tenfold factor, an order of magnitude. Its basic sense is 'digit', so it is not the word for a ten-year period of time.
  医者いしゃなら６桁けたの収入しゅうにゅうは珍めずらしくない。↗

  A six-figure income is not uncommon for physicians.
• 旬じゅんCommon
  nounCovers 'decade' only as a ten-year span of a person's life, counted in one's age. It does not refer to calendar or historical periods such as 'the 1980s'.

Use 桁 for the technical sense of 'decade' — a tenfold factor or order of magnitude — and 旬 for a ten-year span of a person's age; neither covers calendar decades such as 'the 1980s'.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• ディケードdecade
• 歳代さいだいdecade (of age)
• 十年じゅうねんten years
• 桁けたdigit
• 旬じゅんten-year period (in one's age)
• 台だいlevel (e.g. price level)