We don't have a name for anything with wavelengths shorter than gamma rays.
We know that ultra-violet light, X-rays and gamma rays have higher energy (higher frequency and shorter wavelengths) than visible light.
Cosmic rays have shorter wavelength than gamma rays
No, visible light has a lower frequency than gamma rays. Gamma rays are the highest frequency of electromagnetic energy. They are above X-rays.
Ultraviolet light, X-rays, and gamma rays do.
Light waves and X-rays are both forms of electromagnetic energy. X-rays, however, have higher energy (higher frequency and shorter wavelength) than (visible) light.
Both gamma rays and radio waves are part of the electromagnetic spectrum, but gamma rays are much higher frequency (shorter wavelength) than radio waves. Visible light is lower frequency than gamma and higher than radio.
Because they have a shorter wavelength and higher frequency than the other waves and rays in the electromagnetic (EM) spectrum
Because that term is the name we have given to electromagnetic radiation with the highest observed frequency. If they had lower frequency, then we would call them by another name. And if they're called by that name, then they must be rays of the highest observed frequency, all because that is how we have defined them.
Ultraviolet, X-rays, and gamma rays have higher frequency/shorter wavelength than visible light has.
The wavelength is far shorter in gamma rays, and they have a higher frequency, and their photons are much higher in energy than those of microwaves.
Gamma rays
Generally speaking, it is gamma rays that have a higher frequency (and energy) than X-rays. The upper end of the X-ray spectrum and the lower end of the gamma ray spectrum enjoy a bit of overlap, but the X-ray does not have a higher frequency than the gamma ray.