1 metasecond currently equals:
metaseconds have passed since the creation of my metasecond response
Note: Metaseconds are something I created in TWOWrnament Season 2 Round 2, for the prompt "Invent a new measurement. Describe what it does or give an example using it," where I submitted the response "The metasecond. Its length increases by one metasecond every metasecond."
This is what this website is based on. I set the metasecond equal to exactly one second at the point when I submitted the response, although you can set it to be one second at the Unix epoch if you want.