円滑|えんかつenkatsu[0]heiban (flat)

1. na-adjectivesmooth; undisturbed; uninterrupted; harmonious
   彼かれは、中国語ちゅうごくごをしっていたので、私わたしたちは計画けいかくを円滑えんかつに実行じっこうできた。↗

   His knowledge of Chinese enabled us to carry out our plan smoothly.

• Synonym滑らかなめらかNeutralDescribes smooth surfaces or fluent speech, e.g. 「滑らかな肌」「滑らかに話す」; it is about texture and movement, while 「円滑」 is about how affairs proceed.
• SynonymスムーズNeutralLoanword for something going smoothly, e.g. 「スムーズに進む」; common in conversation and more casual than 「円滑」.
• Synonym快調かいちょうNeutralDescribes good condition or smooth running, e.g. 「エンジンが快調だ」; typically used of machines or one's physical condition.
• Related順調じゅんちょうNeutralRefers to progress going well, e.g. 「順調に回復する」; it stresses development as planned, while 「円滑」 stresses an unobstructed process.
• Antonym滞りとどこおりWrittenWritten word for stagnation or delay; the opposite of smooth progress, as in 「滞りなく」.
• Antonym摩擦まさつNeutralFriction or discord between people; the opposite of 「円滑」 in human relations, as in 「貿易摩擦」.

Use 「円滑」 for business or human relations running smoothly without a hitch; it leans written, as in 「円滑な運営」「円滑に進める」. In speech, 「スムーズ」 is the natural choice; for progress as planned use 「順調」. The opposites are 「滞り」 and 「摩擦」.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 丸まるく滑なめらかな状態じょうたいのこと。
2. 物事ものごとが淀よどみなく進行しんこうする様さま。円転えんてん滑脱かつだつ。