chock-full

The term 'chock-full' emerged in Middle English, with its first element 'chock' presenting an etymological puzzle. The most plausible theory traces it to a Northern French dialect word 'choque', meaning a block or a log used as a wedge or stopper. The imagery is of a container so completely packed that a stopper ('chock') could be inserted to secure the contents, leaving no empty space. This literal notion of being blocked or stopped up with contents evolved into the modern, more abstract sense of being absolutely crammed or replete with something, whether tangible or intangible.

The word is a compound of uncertain origin. The first element 'chock' is likely from a dialectal French word 'choquier' or 'choque' meaning a 'block' or 'log', used to stop something. The second element is the English word 'full'.