It is first necessary to establish what, precisely, is being asked by that question, since most casual answers are actually responding to the perceived question ‘how is time measured,’ and not to the actual question ‘what is time’.
In the Time Lords’ Citadel
No, this is not a Dr. Who fanfiction, but I couldn’t resist the allure of what I like to think passes for a clever title for a post about a new change to international standard timekeeping. That’s right: instead of worrying about minor controversies over things like religion, politics, or the Great Pumpkin, what should really be getting your blood pressure up is the CGPM’s vote to abolish the leap second.
IGC Publishing 