serious in intention, purpose, or effort; sincerely zealous

an earnest worker.

showing depth and sincerity of feeling

earnest words; an earnest entreaty.

seriously important; demanding or receiving serious attention.

full seriousness, as of intention or purpose

to speak in earnest.

noun

flippancy , insincerity , unimportance

noun

absorption , ardor , attentiveness , concentration , decision , deliberation , devotion , doggedness , eagerness , engrossment , enthusiasm , fervor , firmness , gravity , intensity , intentness , keenness , passion , perseverance , persistence , purposefulness , resolution , resolve , serious-mindedness , sincerity , sobriety , solemnity , stress , tenacity , urgency , vehemence , warmth , zeal , sobersidedness