"amusement, diversion, that which serves to make the time pass agreeably," late 15c., passe tyme "recreation, diversion, amusement, sport," from pass (v.) + time (n.). Formed on model of French passe-temps (15c.), from passe, imperative of passer "to pass" + temps "time," from Latin tempus (see temporal).
The central idea of a pastime is that it is so positively agreeable that it lets time slip by unnoticed: as, to turn work into pastime. Amusement has the double meaning of being kept from ennui and of finding occasion of mirth .... Recreation is that sort of play or agreeable occupation which refreshes the tired person, making him as good as new. Diversion is a stronger word than recreation, representing that which turns one aside from ordinary serious work or thought, and amuses him greatly. [Century Dictionary, 1895]