Noun
Any word that has a magical effect when uttered.
(in teaching polite behaviour to children) One of the words please, thank you, or hello.
What's the magic word?
(by extension) Any word that is considered very significant in a certain situation or context.
When someone offers you drugs, the magic word is "no".
(computing) A string of text having some special function or purpose.
Coordinate term: magic number
One of the magic words used in the MediaWiki software is __NOTOC__, which hides the table of contents that would normally be on the page.
The show is a satire, which gives us freedom to do anything we want. Satire is the magic word that wipes away any culpability. The media is jealous of this freedom. Rob Corddry
To be powerful in South America, you have to be transparent and you have to have a very clean reputation. Transparency for me today is a magic word in South America. Power comes from transparency and a track record of execution. Eike Batista
Shah is a kind of magic word with the Persian people. Muhammad Reza Pahlavi
You know how teachers tell you the magic word is 'please'? That's not true. The magic word is 'puke'. It will get you out of class faster than anything else. Rick Riordan
.. Africa: it's a magic word that lends itselfs to suppositions and sets amateur explorers to dreaming. I want to try to be 'at home' on this bit of foreign [Arab] soil. Eugène Fromentin