pensive

Engaged in deep and serious thought.

Showing or expressing deep, often melancholy thought.

Engaged in serious thought or reflection; given to earnest musing: often implying some degree of anxiety, depression, or gloom; thoughtful and somewhat melancholy.

Expressing thoughtfulness with sadness; betokening or conducive to thoughtful or earnest musing.

Synonyms Meditative, reflective, sober.