You have a finite set of wages/pay - and $197,000 should be in the middle of this set. Meaning that half the wages at Alphabet are below, the other half above this wage.
It is a rather robust measure, because it is insensitive to extreme values (like the arithmetic average would be), while also giving you a good overview, e.g. that 50% of all the wages are above $197,000.
Vice versa, it tells you nothing about how low or how high the wages are aside the median (e.g. the lower 45% of the wages could be <$45,000). So take it with a grain of salt.