roll ‧ ing /ˈrəʊlɪŋ $ ˈroʊ-/ BrE AmE adjective [only before noun]
[ Word Family: verb : ↑ roll , ↑ unroll ; noun : ↑ roll , ↑ roller ; adjective : ↑ rolling ]
1 . rolling hills have many long gentle slopes
2 . done or happening regularly over a period of time, not all at once:
We recommend a rolling programme of machine upgrading.