per ‧ func ‧ to ‧ ry /pəˈfʌŋkt ə ri $ pər-/ BrE AmE adjective formal
[ Date: 1500-1600 ; Language: Late Latin ; Origin: perfunctorius , from Latin perfunctus , past participle of perfungi 'to get something done' ]
a perfunctory action is done quickly, and is only done because people expect it:
She gave him a perfunctory smile.
The applause was perfunctory.
—perfunctorily adverb