time; years and days; one's life
Refers to the passage of time, often with a poetic or reflective nuance about the accumulation of days, months, and years. Can imply the span of one's life or experiences.
How quickly time passes.
長い月日をかけてこの技術を磨いてきた。
I have spent many years refining this skill.
the Moon and the Sun
Literal reference to the celestial bodies. Often used in poetic or literary contexts. Cross-referenced with 日月 (じつげつ).
See also: 日月
月日は永遠に天空を巡る。
The Moon and the Sun eternally circle the heavens.
He spent long years on that research.
Ten years have flowed by since that incident.
I spent a long span of years together with her.