Blue Bird—is used as a symbolical expression of happiness:
- All these ladies have tried to catch this same Blue Bird.
bluebird—
1. any of several birds that have blue feathers:
- We were fortunate to see such birds as a sky-blue mountain bluebird.
2. (Drug users) a depressant; a blue capsule or tablet containing barbiturate:
- Here, this little bluebird will sing you to sleep.
Note: The compound does not correlate in meaning with the phrase blue canary—an emergency worker (a firefighter or a law enforcement officer) whose death alerts other personnel to a hazardous situation (from the use of canaries in coal mines, whose death would alert miners to the presence of dangerous gases):
- The “blue canaries,” as police and firefighters are sometimes called, would probably suffer heavy casualties until the (chemical) agent is identified.