The word(s) "gentleness" appears 2 time(s) in 2 verse(s) in Quran in Mohsin Khan translation.

(1) And the (faithful) slaves of the Most Gracious (Allah) are those who walk on the earth in humility and sedateness, and when the foolish address them (with bad words) they reply back with mild words of gentleness.

(سورة الفرقان, Al-Furqaan, Chapter #25, Verse #63)
(Arabic, Transliteration, Urdu (Ahmed Ali), Urdu (Jalandhry), Farsi, Yusuf Ali, Shakir, Picthal, Mohsin Khan, French, Spanish, Indonesian, Malay, German, Bosnian, Russian, Dutch, Italian, Portuguese, Tafsir - Jalal ad-Din, Tafsir - King Fahad Quran Complex)

(2) And (the ships) that float with ease and gentleness.

(سورة الذاريات, Adh-Dhaariyat, Chapter #51, Verse #3)
(Arabic, Transliteration, Urdu (Ahmed Ali), Urdu (Jalandhry), Farsi, Yusuf Ali, Shakir, Picthal, Mohsin Khan, French, Spanish, Indonesian, Malay, German, Bosnian, Russian, Dutch, Italian, Portuguese, Tafsir - Jalal ad-Din, Tafsir - King Fahad Quran Complex)