Another nickname is “the fuzz”, which I gather is derived from “the Feds”. Many years ago, one of Edinburgh’s folk clubs took place in the Police social club premises, so it was referred to as The Fuzz Folk Club. Then Ian Green, who founded Greentrax recordings after he retired from being a serving police offer, wrote his autobiography, which he entitled “Fuzz to Folk”. (None of this is particularly peeving, by the way!)