Definition
"Antemeridian" (often written as 'a.m.') refers to the period from midnight to noon. It signifies the time before the sun reaches its highest point in the sky. Think of it as the first half of the day. βοΈ It is usually associated with morning activities. Unlike postmeridian (p.m.), it encompasses the hours when the sun is rising. It's a simple way to differentiate between the morning and the afternoon/evening. So, 3 a.m. is antemeridian, but 3 p.m. is not.