hair·split·ting 
/ˈheɚˌsplɪtɪŋ/ noun
/ˈheɚˌsplɪtɪŋ/ noun [noncount] : the act of arguing about differences that are too small to be important
▪ The lawyers have been engaging in legalistic hairsplitting. — see also split hairs at hair
▪ The lawyers have been engaging in legalistic hairsplitting. — see also split hairs at hair
— hairsplitting adjective
▪ lawyers making hairsplitting distinctions
▪ lawyers making hairsplitting distinctions
