Minecraft wiki entry for time, associated text: Specifies the time to query. Must be daytime, gametime or day.
daytime - the number of game ticks since dawn. (the internal daytime modulo 24000)
gametime - the age of the world in game ticks. (the game time modulo 2147483647)
day - the number of in-game days passed. (the internal daytime divided by 24000, then modulo 2147483647)