Douglas Harper's Etymology Dictionary
"Carbon-14," 1940, from radio-, comb. form of radioactive, + carbon. Radio-carbon dating is attested from 1949.
Usage examples of "radio-carbon".
By radio-carbon date-checking against trees of known age - notably the bristlecone pine which grows in the White Mountains of California, some of which are known to be over 6,000 years old - it has been found that all radio-carbon dates prior to 1000 BC are too young.
Careful sifting through the legends of the Ponapeans, together with analysis by radio-carbon methods, has now produced the estimate that Nan Matol was built in approximately AD 1400 - or rather from AD 1400 onwards, since it was added to by successive kings, who had the title of Satalur.
Samples of that stuff, rocketed up to the ship, would give a reliable estimate, by radio-carbon dating, of how long ago this building had been occupied.