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.
Patience (or forbearing) is the state of endurance under difficult circumstances, which can mean persevering in the face of delay or provocation without acting on negative annoyance/anger; or exhibiting forbearance when under strain, especially when faced with longer-term difficulties.