gully
ˈɡʌli
noun
a ravine formed by the action of water.
ravine,canyon,gorge,pass,defile,couloir,deep narrow valley,gulf,chasm,abyss,chine,bunny,clough,gill,thrutch,cleuch,heugh,gulch,coulee,flume,sloot,kloof,donga
verb
(of water) make gullies or deep channels in (land).
the track was gulleyed by rain