The word 分秒必争 is formed by sequentially combining four characters: 分 (minute), 秒 (second), 必 (must), and 争 (strive or contend). The first two characters denote the smallest common units of time, which are then directly modified by the last two characters to create an imperative structure, resulting in the literal meaning "every minute and second must be striven for", expressing urgency in time management.