The letter K had no particular significance; it was chosen merely to have a phonetically different letter from the letters C and D.
'k' is the standard SI prefix for kilo, meaning multiply by 10^3, or 1000. This is the same as km, meaning kilometer, as in 1000 meters. Your example is kilo Watt hours, as a measure of power usage.
It means konstipaded over weight out of style looser for aboy it means konstipaded over weight out of shape looser
Thousand.
AKA is short for "Also Known As" and denotes aliases used by someone.