crestfallen
Very sad and disappointed, with your feelings clearly showing.
Crestfallen means visibly disappointed or dejected, with your sadness showing plainly on your face and in your posture. The word creates a picture of someone whose head droops and whose whole body sags with disappointment.
Imagine a student who studied hard for the spelling bee, confidently spelled words round after round, then suddenly misspelled an easy word and got eliminated. That sinking feeling, the slumped shoulders, the way their face falls: that's crestfallen. Or picture a young athlete who trained all season, expecting to make the championship team, only to find their name missing from the final roster.
The word comes from roosters, whose bright red crests stand tall when they're confident but droop when they're defeated. A crestfallen person looks like a rooster after losing a fight: deflated, discouraged, and obviously unhappy.
Crestfallen is stronger than simply disappointed. It suggests that the letdown is visible to everyone around you, written across your face and body language. When your best friend arrives at your house looking crestfallen, you don't need to ask if something went wrong. You can see it immediately.