pensive

As adjectives the difference between unreliable and pensive

is that unreliable is not reliable while pensive is having the appearance of deep, often melancholic, thinking.

As adjectives the difference between pensive and feckless

is that pensive is having the appearance of deep, often melancholic, thinking while feckless is lacking purpose.

As an adjective pensive

is having the appearance of deep, often melancholic, thinking.

As a verb disappoint is

to displease by e.g. underperforming.

As an adjective pensive

is having the appearance of deep, often melancholic, thinking.

As a verb worry is

to seize or shake by the throat, especially of a dog or wolf.

As a noun worry is

a strong feeling of anxiety.

As adjectives the difference between pensive and frivolous

is that pensive is having the appearance of deep, often melancholic, thinking while frivolous is silly, especially at an inappropriate time or in an inappropriate manner.

As an adjective pensive

is having the appearance of deep, often melancholic, thinking.

As a verb cogitate is

to meditate, to ponder, to think deeply.

As adjectives the difference between facetious and pensive

is that facetious is treating serious issues with deliberately inappropriate humour; flippant while pensive is having the appearance of deep, often melancholic, thinking.

As adjectives the difference between despondent and pensive

is that despondent is in low spirits from loss of hope or courage while pensive is having the appearance of deep, often melancholic, thinking.

As adjectives the difference between gloomy and pensive

is that gloomy is imperfectly illuminated; dismal through obscurity or darkness; dusky; dim; clouded while pensive is having the appearance of deep, often melancholic, thinking.

As adjectives the difference between sullen and pensive

is that sullen is having a brooding ill temper; sulky while pensive is having the appearance of deep, often melancholic, thinking.

As a noun sullen

is one who is solitary, or lives alone; a hermit.