Byron's mathematician daughter (3)
I believe the answer is:
ada
'byron's mathematician daughter' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for ada that I've seen before include "Novel by Vladimir Nabokov" , "- Lovelace, Byron's daughter & computer pioneer" , "Girl's name, one letter short of a man's name" , "Computer language; girl's name" , "Programming language" .)