noun and transitive verb — spymarked, spymarking; spymarking n., spymarked adj. coined elsewhere
SPY·mark
A hidden signal embedded in media to trace its origin, tools, or distribution history without the user's meaningful control. As a verb, to embed one; spymarking, the practice; spymarked, bearing one.
The spymarks tied each copy to a different recipient.
Etymologyspy + mark, cast in the mould of watermark. English keeps a whole series of -mark compounds for marks that certify — hallmark, from the assay office at Goldsmiths' Hall; trademark; postmark; benchmark; watermark itself, the papermaker's device seen against the light. Every one of them is a mark made to be seen, and the seeing is what confers the trust. spymark joins the series and inverts it: the first -mark made not to be seen, extracting information instead of declaring it.
NoteCoined 21 September 2026, in an essay titled Spymarks, not Watermarks, and the coinage is the argument: watermark implies something visible, declared and benign, and the things being deployed — SynthID, audio beacons, printer dots, provenance manifests — are none of those. Rename them and, in the author's words, the privacy concern is built into the word. This is the counter-move to half of this lexicon. thermobarically and the -ification words show grammar being used to hide an act; spymark is naming used to unhide one. The surveillance was already there — the word makes it audible. It also arrived complete. Most coinages show up as a single form and grow their paradigm over years; this one shipped as a full dictionary family on day one — noun, transitive verb, gerund, participial adjective, each with its example sentence. The social network spymarks every uploaded image. Removing the file's metadata still left the image spymarked. Zero-derivation straight to the verb, exactly the path watermark took, walked in an afternoon instead of a century. And it took two days to stop being hypothetical: front page of Hacker News on the 22nd, follow-up coverage, and tools on GitHub named for it. Every other word here waits on the leaderboard for a second sighting. This one arrived with five.
Documented uses outside this project.
The coining essay: the definition, the case against watermark, and the full word family set out in dictionary form.
The essay discussed under its own title; the word used in comments as an ordinary noun and verb.
Story syndicated under the coinage: “Spymarks, Not Watermarks”.
Explainer adopting the term: “Spymarks: The Hidden Trackers in Your AI Outputs”.
Tools named for the word within days of the essay: spymark-remover, and a SpyMark defence project.