An example of someone who would be dejected is someone who has just lost his job and who is feeling very low.
"Apparently I was wrong," he said in a dejected tone.
Connor responded with a dejected, "Hi."
The despairing, dejected expression of Natasha's face caught his eye.
Kutuzov, dejected and frowning, sat on a bench by the bridge toying with his whip in the sand when a caleche dashed up noisily.
I put the phone down and felt quite dejected.