in lo ‧ co pa ‧ ren ‧ tis /ɪn ˌləʊkəʊ pəˈrentɪs $ -ˌloʊkoʊ-/ BrE AmE adverb formal or law
[ Date: 1700-1800 ; Language: Latin ; Origin: 'in the place of a parent' ]
having the responsibilities of a parent for someone else’s child ⇨ guardian :
As a teacher, you should regard yourself as being in loco parentis.