na-adjective
chronological; over time; temporal
Describes changes, observations, or processes that occur or are tracked over time. Often used in medical, scientific, or technical contexts.
患者の症状を経時的に観察した。
We observed the patient's symptoms over time.
このグラフは経時的な変化を示している。
This graph shows chronological changes.
Compound of 経時 (けいじ, 'passage of time') + 的 (てき, '-like, -al'). The exact historical derivation is uncertain; the spelling is conventionally associated with the meaning.