Synonyms of seriously

1 Syllable
down
2 Syllables
deeply, sternly
3 Syllables
studiously, earnestly, solemnly, busily, rowdily, somberly, gravely, mournfully, intently, movingly, soberly, frightfully, thoughtfully, zealously, heartily, fervently, terribly, mortally, horribly
4 Syllables
sedately, diligently, actively, boisterously, dangerously, affectingly, severely, vigorously, staggeringly, unweariedly, vigilantly, alarmingly, critically, drastically, sincerely, disturbingly
5 Syllables
determinedly, animatedly, resolutely, impressively, perseveringly, purposefully, discouragingly, passionately, desperately, unsecurely
6 Syllables
indefatigably