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 Strenuous Life is the name of a speech given by Theodore Roosevelt in Chicago, Illinois on April 10, 1899. Based upon his personal experiences, he argued that strenuous effort and overcoming hardship were ideals to be embraced by Americans for the betterment of the nation and the world in the 20th century.