stego
v. To hide secret information electronically by embedding it inside an ordinary file such as an image or sound clip.
Etymology
Examples
2001
Something is 'stegoed' in the wired world when encrypted words, diagrams, maps or images are embedded into an existing electronic image, text or audio file. The hidden information is invisible and available only to somebody who knows it's there, how to get it and how to unscramble it.
—Krista Foss, “Does the medium conceal the message?,” The Globe and Mail, October 27, 2001
2001 (earliest)
When a message is encrypted, its contents are more or less jumbled in order to baffle anyone who might intercept it. But if something is 'stegoed,' it is secreted out of sight, like invisible ink. No one but the sender and recipient know it's there, making its discovery much less likely. When used together, the two techniques, encryption and steganography, pose a double whammy for code-breakers.

With the Internet, steganography has come of age. Stego-tools — free and easily downloadable software programs — take advantage of the unused space in audio, text, image, or video files and create a secret hiding place for embedding data. Take an image of Osama bin Laden, for example. Then take a map. A stego-tool can be used to hide the map file under the 'cover image' (stego-speak for the original file). You have the digital age equivalent of invisible ink.
—Catherine Auer, “Behind the bits; steganography used for subversive activities,” Bulletin of the Atomic Scientists, May 01, 2001
Notes
Today's verb is a clipped form of the word steganography — the arcane art of concealed writing (literally, "covered writing") — which has been secreted within the English lexicon for over 400 years. Its tenure as a verb is considerably more recent. I've seen it in Usenet posts from 1995, but as far as the mainstream media goes, the verb seems to have only shown itself this year.
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