specialisation

nouns

(biology) the structural adaptation of some body part for a particular function
"cell differentiation in the developing embryo"
differentiation, specialisation, specialization
is derived from
specialise
the act of specializing; making something suitable for a special purpose
specialisation, specialization
is derived from
specialise
the special line of work you have adopted as your career
"his specialization is gastroenterology"
specialisation, specialism, speciality, specialization, specialty
is derived from
specialise