adjective

blue

Feeling sad or unhappy.

He feels blue after saying goodbye to his closest friend.

Etymology

French bleu supplies the color word. English developed a figurative association between blue and low spirits, so feeling blue describes sadness rather than a literal change in color.

More examples

  • Rainy weekends sometimes leave her blue.
  • I was feeling a little blue yesterday.
  • A friendly call lifted his blue mood.

Forms

blue

Similar words

sad
The ordinary word without the informal color metaphor.
melancholy
Melancholy suggests a quieter or more reflective sadness.