This would mean having a designation for areas with a very high density of Welsh speakers, and a further designation for areas with a high (but lower) density of Welsh speakers.
Byddai hyn yn golygu cael dynodiad ar gyfer ardaloedd â dwysedd uchel iawn o siaradwyr Cymraeg, a dynodiad arall ar gyfer ardaloedd â dwysedd uchel (ond is) o siaradwyr Cymraeg.