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.
See all translations. uk â /ËÉË.dÊu.És/ us â /ËÉËr.dÊu.És/. âº difficult, needing a lot of effort and energy: an arduous climb/task/journey.