Gradually
Steadily, Quietly, Slowly
adverb, の adjective
じょじょ
段々 (だんだん) Gradually, Steps
徐々 (じょじょ) Gradually, Steadily, Quietly, Slowly
どんどん (kana only、not on WK) Rapidly, Quickly, Steadily
着々 (ちゃくちゃく) Steadily
静々 (しずしず) Quietly, Calmly
悠々 (ゆうゆう) Quiet, Calm, Leisurely, Easy
徐行 (じょこう) Going Slowly
JoJo's じょじょ Bizarre Adventure has been Steadily growing in popularity since 1987.