Two entries with the name Cadrieth.
Cadrieth
‘Fair Speech,’ ‘Fine Speech’
Cadriet, Caydryeith, Chadreith
Son of Seidi and one of Arthur’s warriors in Welsh legend. He was the brother of Alun of Dyfed and Cas.
Although a young man, he was one of Arthur’s most trusted advisors because of his keen intellect. In a Welsh Triad he appears with Fflewdur Fflam as one of the Three Chieftains of Arthur’s Court and he was one of the three most courteous to both guests and strangers.
Sources
Triads of the Island of Britain (Welsh ”Triads”) | 11th century to 14th century
Breudwyt Rhonabwy | 13th century
Cadrieth
Son of Gandwy, and one of Arthur’s squires. He held the position of chamberlain and guarded the king’s bed.
Source
Geraint and Enid | 13th century