WCBS AM radio was originally licensed to Springfield Illinois but
when the CBS radio network was formed, a deal was made to change the
call letters in Springfield so New York could get WCBS. The
Springfield calls were changed to WCVS and until the 1980's the
station logo included an asterisk over the V and a small print
addition at the bottom to say 'formerly WCBS'.

WTMC in Ocala Florida, the first radio station there, stood for
Welcome To Marion County. Calls were changed in the nineties.

WXCV FM in Crystal River, Florida calls were invented by one of the
owners. Because the station was at 95 on the FM dial, roman numberals
were used for 95. XC=90 V=5

WHBO AM in Tampa Bay was designed to spell out Hillsborough, the
county of license.

WAFC in Clewiston Florida was picked by one of the founders from the
AFC switch (automatic freq control??) located on the front panel of
the GE Super Radio unit.

WSMD (long since gone) in Chicago was a jazz station that supposedly
stood for Smack Dab in the Middle as they were in the middle of the FM
dial (exact freq I dont recall, but around 98)