Dark pattern
Etymology
Coined in 2010 by the UX researcher Harry Brignull. "Pattern" comes from design’s "pattern library" of reusable solutions; "dark" marks the ones built against the user’s interest — a deliberately ironic twist on a wholesome design term.
noun · /DARK PAT-urn/
A user-interface design deliberately built to trick you into doing something you didn’t intend.
What it names
The named enemy of the maze-like checkout, the buried unsubscribe, the pre-ticked box — deception dressed up as design.
Example
The pre-checked "add insurance" box at checkout is a dark pattern — designed to be missed.
Related idea
Dark patterns are a symptom of enshittification — the platform’s interests turning against yours.