1
general::
Phrase(s): *free as a bird [and] *free as (the) air
Cliché carefree; completely free and unhindered. (*Also: as ~.) • Jane is always happy and free as a bird. • The convict escaped from jail and was as free as a bird for two days. • No, I’m not married. I don’t even have a girlfriend. I’m free as the air.
McGrawhill's American Idioms And Phrasal Verbs
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general::
At liberty, without obligations, as in Can you join us tonight?? Yes, I'm free as a bird, or He's free as a bird? he can travel wherever he chooses. [c. 1700]. Also see FOOTLOOSE AND FANCY-FREE.
American Heritage Idioms