adverb taking the 'to' particle
easily; effortlessly; suddenly; utterly
Describes an action happening smoothly, without resistance, or a sudden, complete change. Often used with verbs like 変わる, 寝る, 落ちる, or 忘れる.
疲れていたので、ベッドに入るところりと寝てしまった。
I was so tired that I fell asleep effortlessly as soon as I got into bed.
His attitude changed completely.
adverb taking the 'to' particle
changing completely
Emphasizes a total transformation, often in character, opinion, or state. Overlaps with sense 1 but highlights the completeness of the change.
あの人は昨日と言っていることがころりと変わった。
What that person says has completely changed from yesterday.
noun
plink; light rolling or falling sound
Mimetic noun for a light, crisp sound of something small falling or rolling, like a coin or a small object.
硬貨が床に落ちて、ころりと音を立てた。
The coin fell on the floor and made a plink sound.
Mimetic word derived from the sound or sensation of something rolling or turning over smoothly. The exact origin is uncertain.