相対年代

そうたいねんだい

noun

•

relative age

相	inter-, mutual, together, each other, minister of state, councillor, aspect, phase, physiognomy
対	vis-a-vis, opposite, even, equal, versus, anti-, compare
年	year, counter for years
代	substitute, change, convert, replace, period, age, counter for decades of ages, eras, etc., generation, charge, rate, fee