AM and PM are associated with 12-hour timekeeping, as opposed to the international 24-hour clock. The 12-hour system grew up mainly in Northern Europe, and spread globally from there via the British Empire.
The adjective STRENUOUS has 2 senses: 1. characterized by or performed with much energy or force. 2. taxing to the utmost; testing powers of endurance. Familiarity information: STRENUOUS used as an adjective is rare.
The definition of sinuous is winding or not straight. An example of sinuous used as an adjective is a sinuous highway that is curvy and runs along the coastline. 1  bending, winding, or curving in and out; wavy; serpentine. 2  not straightforward; devious; crooked.  sinuate ()