These are the ones I could find, listed in alphabetical order: kilobase pair, kilobaud, kilobit, kilobyte, kilocurie, kilodalton, kiloelectronvolt, kiloflop, kilofoot, kilogallon, kilogram, kilohertz, kilojoule, kilolumen, kilomaser, kilonewton, kilonova, kiloohm, kiloparsec, kiloroentgen, kilostere, kiloton, kilounit, kilovolt, kilovoltage, kilo-watt/kilowatt, kiloyear

There is no shortest electromagnetic wave. The higher the energy the higher the frequency, the shorter the wavelength. But since the definition of gamma rays "Energy of 100-200 kiloElectronvolt and above" has no upper limit, no matter how short the wave is, it will still be called "gamma ray"