Proper noun
Estuary English
(Britain) A variety of English accent, spreading out from London into the area of the Thames estuary, containing features of received pronunciation, Cockney and other regional accents.
Estuary English has been gaining prominence in recent decades: it has some features of RP and some of Cockney. Source: Internet
It is similar to the West Country dialects heard in SW England, but less removed in sound from the Estuary English of the SE. Source: Internet