1.Definition: an earnest and sincere feeling

Related Noun(s):earnestness, sincerity

Category: Feelings

2.Definition: the quality of arousing fear or distress

"He learned the seriousness of his illness"

Related Noun(s):distressfulness

Category: General

3.Definition: the trait of being serious

"A lack of solemnity is not necessarily a lack of seriousness"

Related Noun(s):earnestness, sincerity

Category: General