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.
Stamina is the physical or mental energy needed to do a tiring activity for a long time. You have to have a lot of stamina to be a top-class dancer. Synonyms: staying power, endurance, resilience, force More Synonyms of stamina.