Knee-on-neck restraint[r]: A controversial technique used in some extreme martial arts and authorized to be used by some police departments. [e]
Semantic Web[r]: Tim Berners-Lee's concept of a "web of knowledge", whereby web-based document contents would be annotated and classified so that computers can parse the classifications and provide search results based on the semantic information (what the content means), rather than simply on matching of text strings. [e]