solemn

As adjectives the difference between solemn and dread

is that solemn is deeply serious and somber while dread is terrible; greatly feared.

As a verb dread is

to fear greatly.

As a noun dread is

great fear in view of impending evil; fearful apprehension of danger; anticipatory terror.

As adjectives the difference between impish and solemn

is that impish is mischievous; of or befitting an imp while solemn is deeply serious and somber.

As an adjective solemn

is deeply serious and somber.

As a verb dignify is

to invest with dignity or honour.

As adjectives the difference between frivolous and solemn

is that frivolous is silly, especially at an inappropriate time or in an inappropriate manner while solemn is deeply serious and somber.

As an adjective solemn

is deeply serious and somber.

As an adverb sincerely is

in a sincere or earnest manner; honestly.

As adjectives the difference between attentive and solemn

is that attentive is paying attention; noticing, watching, listening, or attending closely while solemn is deeply serious and somber.

As a noun earnestness

is the quality of being earnest; sincerity; seriousness.

As an adjective solemn is

deeply serious and somber.

As adjectives the difference between solemn and gravely

is that solemn is deeply serious and somber while gravely is characterised by gravel, pebbles, or small stones.

As an adverb gravely is

in a grave or serious manner.

As adjectives the difference between solemn and melancholy

is that solemn is deeply serious and somber while melancholy is affected with great sadness or depression.

As a noun melancholy is

(historical) black bile, formerly thought to be one of the four "cardinal humours" of animal bodies.

As adjectives the difference between solemn and undefined

is that solemn is deeply serious and somber while undefined is lacking a definition or value.