tsurun
A perfectly smooth surface with no friction — like a peeled boiled egg, a polished stone, or a baby's skin. Things slide right off.
💡Peeling a boiled egg — 'The shell came off and the egg was tsurun smooth.'
ゆで卵の殻がつるんときれいにむけた。
The boiled egg shell peeled off tsurun smoothly.
The polished marble floor was ___ smooth underfoot.
磨かれた大理石の床は足元が○○としていた。