operational research
noun /ˌɒpəreɪʃənl rɪˈsɜːtʃ/,  /ˌɒpəreɪʃənl ˈriːsɜːtʃ/
  /ˌɑːpəreɪʃənl ˈriːsɜːrtʃ/,  /ˌɑːpəreɪʃənl rɪˈsɜːrtʃ/
(also operations research)
 [uncountable] (specialist)- the study of how businesses are organized, in order to make them more efficient