This diminutive of Bridget usually refers to a fussy old woman
[DOC] [TLE] Biddy dictionary definition | biddy defined - YourDictionary [PAR] biddy definition: ... ... a hen; Informal a woman; esp., an elderly woman (usually 
old biddy) regarded ... (pejorative) A woman, especially an old woman; especially 
one regarded as fussy or mean or a ...