alt Hacker NewsOriginally it was defined like that, but it was fairly quickly redefined as the distance between marks on a prototype platinum bar. It's had a couple of other definitions since then, but it's currently defined "by taking the fixed numerical value of the speed of light in vacuum c to be 299 792 458 when expressed in the unit ms⁻¹, where the second is defined in terms of the caesium frequency ΔνCs".
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thaumasiotes • today at 9:32 AM
But that isn't a change to the definition of the meter. What do you think the motivation for the constant 299,792,458 is?
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Yes technically speaking there is a different physical reference now but that's where it came from. A bit like how 1 ft is now 304.8mm but that's because it's the size of a human foot (with some historic details no doubt).
Etymology vs dictionary, I suppose.