What does "vain" mean?
See vain in WNW Idioms
in vain
- fruitlessly; vainly
- lightly; profanely; irreverently
See vain in American Heritage Dictionary 4 Idioms
in vain
- To no avail; without success: Our labor was in vain.
- In an irreverent or disrespectful manner: took the Lord's name in vain.
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