the.com/earnest
Sincerity with its sleeves rolled up — heartfelt, humorless, and trying so hard you almost root for it.
means Showing serious, sincere intention and effort, free of irony or pretense.
from From Old English eornost, meaning seriousness or zeal in battle — back when meaning it could get you killed.
Legal twinEarnest money seals deals with cold cash sincerity.
Wilde's jokeThe Importance of Being Earnest puns on the name Ernest.
Tonal cousinOften the polite word before someone says naive.